[iOS] Remove tab storage on all tab content scripts

This change prepares for using the Chromium web embedder by removing weak storage of `Tab` objects passed in when creating classes confomring to `TabContentScript` which better matches `JavaScriptFeature` and its requirements

ios/brave-ios/Sources/Brave/Frontend/Browser/BraveGetUA.swift

@@ -8,12 +8,6 @@ import Shared
 import WebKit
 
 class BraveGetUA: TabContentScript {
-  fileprivate weak var tab: Tab?
-
-  required init(tab: Tab) {
-    self.tab = tab
-  }
-
   static let scriptName = "BraveGetUA"
   static let scriptId = UUID().uuidString
   static let messageHandlerName = "\(scriptName)_\(messageUUID)"
@@ -34,9 +28,9 @@ class BraveGetUA: TabContentScript {
     )
   }()
 
-  func userContentController(
-    _ userContentController: WKUserContentController,
-    didReceiveScriptMessage message: WKScriptMessage,
+  func tab(
+    _ tab: Tab,
+    receivedScriptMessage message: WKScriptMessage,
     replyHandler: (Any?, String?) -> Void
   ) {
     // 🙀 😭 🏃‍♀️💨

ios/brave-ios/Sources/Brave/Frontend/Browser/BrowserViewController/BVC+ReaderMode.swift

@@ -54,7 +54,7 @@ extension BrowserViewController: ReaderModeStyleViewControllerDelegate {
           as? ReaderModeScriptHandler
         {
           if readerMode.state == ReaderModeState.active {
-            readerMode.style = style
+            readerMode.setStyle(style, in: tab)
           }
         }
       }

ios/brave-ios/Sources/Brave/Frontend/Browser/BrowserViewController/BVC+WKNavigationDelegate.swift

@@ -729,8 +729,7 @@ extension BrowserViewController: WKNavigationDelegate {
 
     // We can only show this content in the web view if this web view is not pending
     // download via the context menu.
-    let canShowInWebView = navigationResponse.canShowMIMEType && (webView != pendingDownloadWebView)
-    let forceDownload = webView == pendingDownloadWebView
+    let canShowInWebView = navigationResponse.canShowMIMEType
 
     let mimeTypesThatRequireSFSafariViewControllerHandling: [UTType] = [
       .textCalendar,
@@ -823,13 +822,8 @@ extension BrowserViewController: WKNavigationDelegate {
       request: request,
       response: response,
       cookieStore: cookieStore,
-      canShowInWebView: canShowInWebView,
-      forceDownload: forceDownload
+      canShowInWebView: canShowInWebView
     ) {
-      // Clear the pending download web view so that subsequent navigations from the same
-      // web view don't invoke another download.
-      pendingDownloadWebView = nil
-
       let downloadAlertAction: (HTTPDownload) -> Void = { [weak self] download in
         self?.downloadQueue.enqueue(download)
       }

ios/brave-ios/Sources/Brave/Frontend/Browser/BrowserViewController/BrowserViewController.swift

@@ -227,10 +227,6 @@ public class BrowserViewController: UIViewController {
   // allow us to re-trigger the `URLRequest` if the user requests a file to be downloaded.
   var pendingRequests = [String: URLRequest]()
 
-  // This is set when the user taps "Download Link" from the context menu. We then force a
-  // download of the next request through the `WKNavigationDelegate` that matches this web view.
-  weak var pendingDownloadWebView: WKWebView?
-
   let downloadQueue = DownloadQueue()
 
   private var cancellables: Set<AnyCancellable> = []
@@ -2615,32 +2611,33 @@ extension BrowserViewController: TabDelegate {
     webView.uiDelegate = self
 
     var injectedScripts: [TabContentScript] = [
-      ReaderModeScriptHandler(tab: tab),
+      ReaderModeScriptHandler(),
       ErrorPageHelper(certStore: profile.certStore),
-      SessionRestoreScriptHandler(tab: tab),
-      BlockedDomainScriptHandler(tab: tab),
-      HTTPBlockedScriptHandler(tab: tab, tabManager: tabManager),
-      PrintScriptHandler(browserController: self, tab: tab),
-      CustomSearchScriptHandler(tab: tab),
-      DarkReaderScriptHandler(tab: tab),
-      FocusScriptHandler(tab: tab),
-      BraveGetUA(tab: tab),
-      BraveSearchScriptHandler(tab: tab, profile: profile, rewards: rewards),
-      ResourceDownloadScriptHandler(tab: tab),
-      DownloadContentScriptHandler(browserController: self, tab: tab),
+      SessionRestoreScriptHandler(),
+      BlockedDomainScriptHandler(),
+      HTTPBlockedScriptHandler(tabManager: tabManager),
+      PrintScriptHandler(browserController: self),
+      CustomSearchScriptHandler(),
+      DarkReaderScriptHandler(),
+      FocusScriptHandler(),
+      BraveGetUA(),
+      BraveSearchScriptHandler(profile: profile, rewards: rewards),
+      ResourceDownloadScriptHandler(),
+      DownloadContentScriptHandler(browserController: self),
       PlaylistScriptHandler(tab: tab),
-      PlaylistFolderSharingScriptHandler(tab: tab),
-      RewardsReportingScriptHandler(rewards: rewards, tab: tab),
-      AdsMediaReportingScriptHandler(rewards: rewards, tab: tab),
-      ReadyStateScriptHandler(tab: tab),
-      DeAmpScriptHandler(tab: tab),
-      SiteStateListenerScriptHandler(tab: tab),
-      CosmeticFiltersScriptHandler(tab: tab),
-      URLPartinessScriptHandler(tab: tab),
-      FaviconScriptHandler(tab: tab),
-      Web3NameServiceScriptHandler(tab: tab),
+      PlaylistFolderSharingScriptHandler(),
+      RewardsReportingScriptHandler(rewards: rewards),
+      AdsMediaReportingScriptHandler(rewards: rewards),
+      ReadyStateScriptHandler(),
+      DeAmpScriptHandler(),
+      SiteStateListenerScriptHandler(),
+      CosmeticFiltersScriptHandler(),
+      URLPartinessScriptHandler(),
+      FaviconScriptHandler(),
+      Web3NameServiceScriptHandler(),
       YoutubeQualityScriptHandler(tab: tab),
-      BraveLeoScriptHandler(tab: tab),
+      BraveLeoScriptHandler(),
+      BraveSkusScriptHandler(),
 
       tab.contentBlocker,
       tab.requestBlockingContentHelper,
@@ -2649,7 +2646,6 @@ extension BrowserViewController: TabDelegate {
     #if canImport(BraveTalk)
     injectedScripts.append(
       BraveTalkScriptHandler(
-        tab: tab,
         rewards: rewards,
         launchNativeBraveTalk: { [weak self] tab, room, token in
           self?.launchNativeBraveTalk(tab: tab, room: room, token: token)
@@ -2658,17 +2654,13 @@ extension BrowserViewController: TabDelegate {
     )
     #endif
 
-    if let braveSkusHandler = BraveSkusScriptHandler(tab: tab) {
-      injectedScripts.append(braveSkusHandler)
-    }
-
     // Only add the logins handler and wallet provider if the tab is NOT a private browsing tab
     if !tab.isPrivate {
       injectedScripts += [
-        LoginsScriptHandler(tab: tab, profile: profile, passwordAPI: braveCore.passwordAPI),
-        EthereumProviderScriptHandler(tab: tab),
-        SolanaProviderScriptHandler(tab: tab),
-        BraveSearchResultAdScriptHandler(tab: tab),
+        LoginsScriptHandler(profile: profile, passwordAPI: braveCore.passwordAPI),
+        EthereumProviderScriptHandler(),
+        SolanaProviderScriptHandler(),
+        BraveSearchResultAdScriptHandler(),
       ]
     }
 

ios/brave-ios/Sources/Brave/Frontend/Browser/FingerprintingProtection.swift

@@ -8,12 +8,6 @@ import Foundation
 import WebKit
 
 class FingerprintingProtection: TabContentScript {
-  fileprivate weak var tab: Tab?
-
-  init(tab: Tab) {
-    self.tab = tab
-  }
-
   static let scriptName = "FingerprintingProtection"
   static let scriptId = UUID().uuidString
   static let messageHandlerName = "\(scriptName)_\(messageUUID)"
@@ -34,15 +28,14 @@ class FingerprintingProtection: TabContentScript {
     )
   }()
 
-  func userContentController(
-    _ userContentController: WKUserContentController,
-    didReceiveScriptMessage message: WKScriptMessage,
+  func tab(
+    _ tab: Tab,
+    receivedScriptMessage message: WKScriptMessage,
     replyHandler: (Any?, String?) -> Void
   ) {
     defer { replyHandler(nil, nil) }
-    if let stats = self.tab?.contentBlocker.stats {
-      self.tab?.contentBlocker.stats = stats.adding(fingerprintingCount: 1)
-      BraveGlobalShieldStats.shared.fpProtection += 1
-    }
+    let stats = tab.contentBlocker.stats
+    tab.contentBlocker.stats = stats.adding(fingerprintingCount: 1)
+    BraveGlobalShieldStats.shared.fpProtection += 1
   }
 }

ios/brave-ios/Sources/Brave/Frontend/Browser/Helpers/OpenInHelper.swift

@@ -57,8 +57,7 @@ class DownloadHelper: NSObject {
     request: URLRequest?,
     response: URLResponse,
     cookieStore: WKHTTPCookieStore,
-    canShowInWebView: Bool,
-    forceDownload: Bool
+    canShowInWebView: Bool
   ) {
     guard let request = request else {
       return nil
@@ -71,7 +70,7 @@ class DownloadHelper: NSObject {
     let isAttachment =
       contentDisposition?.starts(with: "attachment") ?? (mimeType == MIMEType.octetStream)
 
-    guard isAttachment || !canShowInWebView || forceDownload else {
+    guard isAttachment || !canShowInWebView else {
       return nil
     }
 

ios/brave-ios/Sources/Brave/Frontend/Browser/Playlist/Managers & Cache/PlaylistCacheLoader.swift

@@ -153,10 +153,10 @@ class LivePlaylistWebLoader: UIView, PlaylistWebLoader {
     static let userScript: WKUserScript? = nil
     static let playlistProcessDocumentLoad = PlaylistScriptHandler.playlistProcessDocumentLoad
 
-    func userContentController(
-      _ userContentController: WKUserContentController,
-      didReceiveScriptMessage message: WKScriptMessage,
-      replyHandler: (Any?, String?) -> Void
+    func tab(
+      _ tab: Tab,
+      receivedScriptMessage message: WKScriptMessage,
+      replyHandler: @escaping (Any?, String?) -> Void
     ) {
       if !verifyMessage(message: message) {
         assertionFailure("Missing required security token.")

ios/brave-ios/Sources/Brave/Frontend/Browser/Tab.swift

@@ -38,9 +38,9 @@ protocol TabContentScript: TabContentScriptLoader {
   func verifyMessage(message: WKScriptMessage) -> Bool
   func verifyMessage(message: WKScriptMessage, securityToken: String) -> Bool
 
-  func userContentController(
-    _ userContentController: WKUserContentController,
-    didReceiveScriptMessage message: WKScriptMessage,
+  @MainActor func tab(
+    _ tab: Tab,
+    receivedScriptMessage message: WKScriptMessage,
     replyHandler: @escaping (Any?, String?) -> Void
   )
 }
@@ -358,7 +358,7 @@ class Tab: NSObject {
 
   // There is no 'available macro' on props, we currently just need to store ownership.
   lazy var contentBlocker = ContentBlockerHelper(tab: self)
-  lazy var requestBlockingContentHelper = RequestBlockingContentScriptHandler(tab: self)
+  let requestBlockingContentHelper = RequestBlockingContentScriptHandler()
 
   /// The last title shown by this tab. Used by the tab tray to show titles for zombie tabs.
   var lastTitle: String?
@@ -398,7 +398,7 @@ class Tab: NSObject {
   // If this tab has been opened from another, its parent will point to the tab from which it was opened
   weak var parent: Tab?
 
-  fileprivate var contentScriptManager = TabContentScriptManager()
+  fileprivate let contentScriptManager = TabContentScriptManager()
   private var userScripts = Set<UserScriptManager.ScriptType>()
   private var customUserScripts = Set<UserScriptType>()
 
@@ -450,8 +450,10 @@ class Tab: NSObject {
     tabGeneratorAPI: BraveTabGeneratorAPI? = nil
   ) {
     self.configuration = configuration
-    self.favicon = Favicon.default
     self.id = id
+    self.type = type
+
+    self.favicon = Favicon.default
     rewardsId = UInt32.random(in: 1...UInt32.max)
     nightMode = Preferences.General.nightModeEnabled.value
     _syncTab = tabGeneratorAPI?.createBraveSyncTab(isOffTheRecord: type == .private)
@@ -465,7 +467,8 @@ class Tab: NSObject {
     }
 
     super.init()
-    self.type = type
+
+    self.contentScriptManager.tab = self
   }
 
   weak var navigationDelegate: WKNavigationDelegate? {
@@ -625,7 +628,7 @@ class Tab: NSObject {
   }
 
   func deleteWebView() {
-    contentScriptManager.uninstall(from: self)
+    contentScriptManager.uninstall()
 
     if let webView = webView {
       webView.removeObserver(self, forKeyPath: KVOConstants.url.keyPath)
@@ -1053,30 +1056,29 @@ extension Tab: TabWebViewDelegate {
 
 private class TabContentScriptManager: NSObject, WKScriptMessageHandlerWithReply {
   fileprivate var helpers = [String: TabContentScript]()
+  weak var tab: Tab?
 
-  func uninstall(from tab: Tab) {
+  func uninstall() {
     helpers.forEach {
       let name = type(of: $0.value).messageHandlerName
-      tab.webView?.configuration.userContentController.removeScriptMessageHandler(forName: name)
+      tab?.webView?.configuration.userContentController.removeScriptMessageHandler(forName: name)
     }
   }
 
-  @objc func userContentController(
+  func userContentController(
     _ userContentController: WKUserContentController,
     didReceive message: WKScriptMessage,
     replyHandler: @escaping (Any?, String?) -> Void
   ) {
-    for helper in helpers.values {
-      let scriptMessageHandlerName = type(of: helper).messageHandlerName
-      if scriptMessageHandlerName == message.name {
-        helper.userContentController(
-          userContentController,
-          didReceiveScriptMessage: message,
-          replyHandler: replyHandler
-        )
-        return
-      }
+    guard let tab,
+      let helper = helpers.values.first(where: {
+        type(of: $0).messageHandlerName == message.name
+      })
+    else {
+      replyHandler(nil, nil)
+      return
     }
+    helper.tab(tab, receivedScriptMessage: message, replyHandler: replyHandler)
   }
 
   func addContentScript(

ios/brave-ios/Sources/Brave/Frontend/Reader/ReadabilityService.swift

@@ -38,7 +38,7 @@ class ReadabilityOperation: Operation {
       self.tab.createWebview()
       self.tab.navigationDelegate = self
 
-      let readerMode = ReaderModeScriptHandler(tab: self.tab)
+      let readerMode = ReaderModeScriptHandler()
       readerMode.delegate = self
       self.tab.addContentScript(
         readerMode,