Fix the issue that any tab/window closing hotkey will crash the Pepper Flash Fullscreen.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 8256d033f6112937f6cf2299271e2503c2bc632f..4cb28fc969492870b7d5d00da9596cc098d6da47 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -362,6 +362,12 @@ WebContentsImpl::WebContentsImpl(
 WebContentsImpl::~WebContentsImpl() {
   is_being_destroyed_ = true;
 
+  for (std::set<RenderWidgetHostImpl*>::iterator iter =
+           created_widgets_.begin(); iter != created_widgets_.end(); ++iter) {
+    (*iter)->DetachDelegate();
+  }
+  created_widgets_.clear();
+
   // Clear out any JavaScript state.
   if (dialog_creator_)
     dialog_creator_->ResetJavaScriptState(this);
@@ -1161,6 +1167,19 @@ void WebContentsImpl::LostCapture() {
     delegate_->LostCapture();
 }
 
+void WebContentsImpl::RenderWidgetDeleted(
+    RenderWidgetHostImpl* render_widget_host) {
+  if (is_being_destroyed_) {
+    // |created_widgets_| might have been destroyed.
+    return;
+  }
+
+  std::set<RenderWidgetHostImpl*>::iterator iter =
+      created_widgets_.find(render_widget_host);
+  if (iter != created_widgets_.end())
+    created_widgets_.erase(iter);
+}
+
 bool WebContentsImpl::PreHandleKeyboardEvent(
     const NativeWebKeyboardEvent& event,
     bool* is_keyboard_shortcut) {
@@ -1323,6 +1342,8 @@ void WebContentsImpl::CreateNewWidget(int route_id,
   content::RenderProcessHost* process = GetRenderProcessHost();
   RenderWidgetHostImpl* widget_host =
       new RenderWidgetHostImpl(this, process, route_id);
+  created_widgets_.insert(widget_host);
+
   RenderWidgetHostViewPort* widget_view =
       RenderWidgetHostViewPort::CreateViewForWidget(widget_host);
   if (!is_fullscreen) {