Try a new approach to fixing IAT unpatch crashes when the DLL is gone.

webkit/glue/plugins/webplugin_delegate_impl.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "webkit/glue/plugins/webplugin_delegate_impl.h"
 
 #include <string>
 #include <vector>
 
 #include "base/file_util.h"
@@ skipping 137 matching lines @@
       windowless_needs_set_window_(true),
       plugin_wnd_proc_(NULL),
       last_message_(0),
       is_calling_wndproc(false),
       dummy_window_for_activation_(NULL),
       handle_event_message_filter_hook_(NULL),
       handle_event_pump_messages_event_(NULL),
       handle_event_depth_(0),
       user_gesture_message_posted_(false),
 #pragma warning(suppress: 4355)  // can use this
-      user_gesture_msg_factory_(this),
-      plugin_module_handle_(NULL) {
+      user_gesture_msg_factory_(this) {
   memset(&window_, 0, sizeof(window_));
 
   const WebPluginInfo& plugin_info = instance_->plugin_lib()->plugin_info();
   std::string filename =
       WideToUTF8(StringToLowerASCII(plugin_info.path.BaseName().value()));
 
   if (instance_->mime_type() == "application/x-shockwave-flash" ||
       filename == "npswf32.dll") {
     // Flash only requests windowless plugins if we return a Mozilla user
     // agent.
@@ skipping 24 matching lines @@
     // handle
     quirks_ |= PLUGIN_QUIRK_DONT_SET_NULL_WINDOW_HANDLE_ON_DESTROY;
     // VLC 0.8.6d and 0.8.6e crash if multiple instances are created.
     quirks_ |= PLUGIN_QUIRK_DONT_ALLOW_MULTIPLE_INSTANCES;
   } else if (filename == "npctrl.dll") {
     // Explanation for this quirk can be found in
     // WebPluginDelegateImpl::Initialize.
     quirks_ |= PLUGIN_QUIRK_PATCH_TRACKPOPUP_MENU;
     quirks_ |= PLUGIN_QUIRK_PATCH_SETCURSOR;
   }
-
-  plugin_module_handle_ = ::GetModuleHandle(plugin_info.path.value().c_str());
 }
 
 WebPluginDelegateImpl::~WebPluginDelegateImpl() {
   if (::IsWindow(dummy_window_for_activation_)) {
     ::DestroyWindow(dummy_window_for_activation_);
     TRACK_HWND_DESTRUCTION(dummy_window_for_activation_);
   }
 
   DestroyInstance();
 
@@ skipping 60 matching lines @@
   // WindowFromPoint API and passes the result of that to the
   // TrackPopupMenu API call as the owner window. This causes the API
   // to fail as the API expects the window handle to live on the same
   // thread as the caller. It works in the other browsers as the plugin
   // lives on the browser thread. Our workaround is to intercept the
   // TrackPopupMenu API for Silverlight and replace the window handle
   // with the dummy activation window.
   if (windowless_ && !g_iat_patch_track_popup_menu.Pointer()->is_patched() &&
       (quirks_ & PLUGIN_QUIRK_PATCH_TRACKPOPUP_MENU)) {
     g_iat_patch_track_popup_menu.Pointer()->Patch(
-        plugin_module_handle_, "user32.dll", "TrackPopupMenu",
+        GetPluginPath().value().c_str(), "user32.dll", "TrackPopupMenu",
         WebPluginDelegateImpl::TrackPopupMenuPatch);
   }
 
   // Windowless plugins can set cursors by calling the SetCursor API. This
   // works because the thread inputs of the browser UI thread and the plugin
   // thread are attached. We intercept the SetCursor API for windowless plugins
   // and remember the cursor being set. This is shipped over to the browser
   // in the HandleEvent call, which ensures that the cursor does not change
   // when a windowless plugin instance changes the cursor in a background tab.
   if (windowless_ && !g_iat_patch_set_cursor.Pointer()->is_patched() &&
       (quirks_ & PLUGIN_QUIRK_PATCH_SETCURSOR)) {
     g_iat_patch_set_cursor.Pointer()->Patch(
-        plugin_module_handle_, "user32.dll", "SetCursor",
+        GetPluginPath().value().c_str(), "user32.dll", "SetCursor",
         WebPluginDelegateImpl::SetCursorPatch);
   }
   return true;
 }
 
 void WebPluginDelegateImpl::DestroyInstance() {
   if (instance_ && (instance_->npp()->ndata != NULL)) {
     // Shutdown all streams before destroying so that
     // no streams are left "in progress".  Need to do
     // this before calling set_web_plugin(NULL) because the
@@ skipping 885 matching lines @@
 
   // It is ok to pass NULL here to GetCursor as we are not looking for cursor
   // types defined by Webkit.
   HCURSOR previous_cursor =
       g_current_plugin_instance->current_windowless_cursor_.GetCursor(NULL);
 
   g_current_plugin_instance->current_windowless_cursor_.InitFromExternalCursor(
       cursor);
   return previous_cursor;
 }