Improve timing of frame attach/detach (see #3664)

- Move frame attachment from RenderFrameCreated to
  DidCommitProvisionalLoad. This has a number of advantages:
  - Significantly reduces the frequency of disconnects by avoiding
    the GetInterface/DidCommitNavigation race condition.
  - Stops connecting temporary frames (created during cross-origin
    navigation), making callback behavior more consistent.
- Split frame detach and destruction notifications into separate
  callbacks. OnFrameDetached now reflects a potentially recoverable
  state. Add a new OnFrameDestroyed callback for the unrecoverable
  destruction state.

libcef_dll/cpptoc/frame_handler_cpptoc.cc

@@ -9,7 +9,7 @@
 // implementations. See the translator.README.txt file in the tools directory
 // for more information.
 //
-// $hash=4a3d33abbaa00a373ea515338ed67d96708dbb9c$
+// $hash=51da21d569dd41e38cb2dc6e0f2dea0bd88dbdce$
 //
 
 #include "libcef_dll/cpptoc/frame_handler_cpptoc.h"
@@ -50,6 +50,34 @@ frame_handler_on_frame_created(struct _cef_frame_handler_t* self,
       CefBrowserCToCpp::Wrap(browser), CefFrameCToCpp::Wrap(frame));
 }
 
+void CEF_CALLBACK
+frame_handler_on_frame_destroyed(struct _cef_frame_handler_t* self,
+                                 cef_browser_t* browser,
+                                 cef_frame_t* frame) {
+  shutdown_checker::AssertNotShutdown();
+
+  // AUTO-GENERATED CONTENT - DELETE THIS COMMENT BEFORE MODIFYING
+
+  DCHECK(self);
+  if (!self) {
+    return;
+  }
+  // Verify param: browser; type: refptr_diff
+  DCHECK(browser);
+  if (!browser) {
+    return;
+  }
+  // Verify param: frame; type: refptr_diff
+  DCHECK(frame);
+  if (!frame) {
+    return;
+  }
+
+  // Execute
+  CefFrameHandlerCppToC::Get(self)->OnFrameDestroyed(
+      CefBrowserCToCpp::Wrap(browser), CefFrameCToCpp::Wrap(frame));
+}
+
 void CEF_CALLBACK
 frame_handler_on_frame_attached(struct _cef_frame_handler_t* self,
                                 cef_browser_t* browser,
@@ -140,6 +168,7 @@ frame_handler_on_main_frame_changed(struct _cef_frame_handler_t* self,
 
 CefFrameHandlerCppToC::CefFrameHandlerCppToC() {
   GetStruct()->on_frame_created = frame_handler_on_frame_created;
+  GetStruct()->on_frame_destroyed = frame_handler_on_frame_destroyed;
   GetStruct()->on_frame_attached = frame_handler_on_frame_attached;
   GetStruct()->on_frame_detached = frame_handler_on_frame_detached;
   GetStruct()->on_main_frame_changed = frame_handler_on_main_frame_changed;

libcef_dll/ctocpp/frame_handler_ctocpp.cc

@@ -9,7 +9,7 @@
 // implementations. See the translator.README.txt file in the tools directory
 // for more information.
 //
-// $hash=0074492ed580ccc06962a05b6c72bdabae182a51$
+// $hash=14e4a39489488582d7965ae71ed1ef174a4f3b08$
 //
 
 #include "libcef_dll/ctocpp/frame_handler_ctocpp.h"
@@ -48,6 +48,34 @@ void CefFrameHandlerCToCpp::OnFrameCreated(CefRefPtr<CefBrowser> browser,
                             CefFrameCppToC::Wrap(frame));
 }
 
+NO_SANITIZE("cfi-icall")
+void CefFrameHandlerCToCpp::OnFrameDestroyed(CefRefPtr<CefBrowser> browser,
+                                             CefRefPtr<CefFrame> frame) {
+  shutdown_checker::AssertNotShutdown();
+
+  cef_frame_handler_t* _struct = GetStruct();
+  if (CEF_MEMBER_MISSING(_struct, on_frame_destroyed)) {
+    return;
+  }
+
+  // AUTO-GENERATED CONTENT - DELETE THIS COMMENT BEFORE MODIFYING
+
+  // Verify param: browser; type: refptr_diff
+  DCHECK(browser.get());
+  if (!browser.get()) {
+    return;
+  }
+  // Verify param: frame; type: refptr_diff
+  DCHECK(frame.get());
+  if (!frame.get()) {
+    return;
+  }
+
+  // Execute
+  _struct->on_frame_destroyed(_struct, CefBrowserCppToC::Wrap(browser),
+                              CefFrameCppToC::Wrap(frame));
+}
+
 NO_SANITIZE("cfi-icall")
 void CefFrameHandlerCToCpp::OnFrameAttached(CefRefPtr<CefBrowser> browser,
                                             CefRefPtr<CefFrame> frame,

libcef_dll/ctocpp/frame_handler_ctocpp.h

@@ -9,7 +9,7 @@
 // implementations. See the translator.README.txt file in the tools directory
 // for more information.
 //
-// $hash=a571fa8b3c173d78cfb67eb3e44c8f2c3fb2e089$
+// $hash=f33fedc6d7e0d692b03fe7f35319e93c5f31b9b1$
 //
 
 #ifndef CEF_LIBCEF_DLL_CTOCPP_FRAME_HANDLER_CTOCPP_H_
@@ -36,6 +36,8 @@ class CefFrameHandlerCToCpp : public CefCToCppRefCounted<CefFrameHandlerCToCpp,
   // CefFrameHandler methods.
   void OnFrameCreated(CefRefPtr<CefBrowser> browser,
                       CefRefPtr<CefFrame> frame) override;
+  void OnFrameDestroyed(CefRefPtr<CefBrowser> browser,
+                        CefRefPtr<CefFrame> frame) override;
   void OnFrameAttached(CefRefPtr<CefBrowser> browser,
                        CefRefPtr<CefFrame> frame,
                        bool reattached) override;