fix(agent): revert zend_try/catch php call logic (#811)

zend_try/zend_catch is to handle Zend Exceptions not PHP exceptions -
see
[here](https://github.com/newrelic/newrelic-php-agent/blob/320ea571a11bc469d7d8179dfe51577b54df11df/agent/php_user_instrument.c#L17-L50)
for more details. They were added in this
[commit](66eccf7)
to handle misbehaving PHP embed SAPI that threw Zend Exception when PHP
code that was called via nr_php_call threw PHP Exception. PHP CLI or CGI
SAPIs don’t throw Zend Exception when PHP code that was called threw PHP
Exception and therefore zend_try/zend_catch is effectively a dead code.

agent/php_call.c

@@ -10,56 +10,6 @@
 
 #include "Zend/zend_exceptions.h"
 
-/*
- * zend_try family of macros entail the use of setjmp and longjmp, which can cause clobbering issues with
- * non-primitive local variables. Abstracting these constructs into separate functions protects from this.
- */
-#if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
-static int nr_php_call_try_catch(zend_object* object,
-                                 zend_string* method_name,
-                                 zval* retval,
-                                 zend_uint param_count,
-                                 zval* param_values) {
-  /*
-   * With PHP 8.2, functions that do not exist will cause a fatal error to
-   * be thrown. `zend_call_method_if_exists` will attempt to call a function and
-   * silently fail if it does not exist
-   */
-  int zend_result = FAILURE;
-  zend_try {
-    zend_result = zend_call_method_if_exists(object, method_name, retval,
-                                             param_count, param_values);
-  }
-  zend_catch { zend_result = FAILURE; }
-  zend_end_try();
-  return zend_result;
-}
-#elif ZEND_MODULE_API_NO < ZEND_8_2_X_API_NO \
-    && ZEND_MODULE_API_NO >= ZEND_8_0_X_API_NO
-static int nr_php_call_try_catch(zval* object_ptr,
-                                 zval* fname,
-                                 zval* retval,
-                                 zend_uint param_count,
-                                 zval* param_values) {
-  /*
-   * With PHP8, `call_user_function_ex` was removed and `call_user_function`
-   * became the recommended function.
-   * According to zend internals documentation:
-   * As of PHP 7.1.0, the function_table argument is not used and should
-   * always be NULL. See for more details:
-   * https://www.phpinternalsbook.com/php7/internal_types/functions/callables.html
-   */
-  int zend_result = FAILURE;
-  zend_try {
-    zend_result = call_user_function(EG(function_table), object_ptr, fname,
-                                     retval, param_count, param_values);
-  }
-  zend_catch { zend_result = FAILURE; }
-  zend_end_try();
-  return zend_result;
-}
-#endif
-
 zval* nr_php_call_user_func(zval* object_ptr,
                             const char* function_name,
                             zend_uint param_count,
@@ -116,18 +66,24 @@ zval* nr_php_call_user_func(zval* object_ptr,
   }
 
   /*
-   * For PHP 8+, in the case of exceptions according to:
-   * https://www.php.net/manual/en/function.call-user-func.php
-   * Callbacks registered with functions such as call_user_func() and
-   * call_user_func_array() will not be called if there is an uncaught exception
-   * thrown in a previous callback. So if we call something that causes an
-   * exception, it will block us from future calls that use call_user_func or
-   * call_user_func_array and hence the need for a try/catch block.
+   * With PHP 8.2, functions that do not exist will cause a fatal error to
+   * be thrown. `zend_call_method_if_exists` will attempt to call a function and
+   * silently fail if it does not exist
    */
-  zend_result =  nr_php_call_try_catch(object, method_name, retval, param_count, param_values);
+  zend_result =  zend_call_method_if_exists(object, method_name, retval, param_count, param_values);
+
 #elif ZEND_MODULE_API_NO < ZEND_8_2_X_API_NO \
     && ZEND_MODULE_API_NO >= ZEND_8_0_X_API_NO
-  zend_result = nr_php_call_try_catch(object_ptr, fname, retval, param_count, param_values);
+    /*
+   * With PHP8, `call_user_function_ex` was removed and `call_user_function`
+   * became the recommended function.
+   * According to zend internals documentation:
+   * As of PHP 7.1.0, the function_table argument is not used and should
+   * always be NULL. See for more details:
+   * https://www.phpinternalsbook.com/php7/internal_types/functions/callables.html
+   */
+  zend_result = call_user_function(EG(function_table), object_ptr, fname,
+                                     retval, param_count, param_values);
 
 #else
   zend_result = call_user_function_ex(EG(function_table), object_ptr, fname,