Fix autofill popup controller key press callback registration

chrome/browser/ui/autofill/popup_controller_common.cc

 // Copyright 2014 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 "chrome/browser/ui/autofill/popup_controller_common.h"
 
-#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
 
 namespace autofill {
 
+namespace {
+
+content::RenderWidgetHost* KeyPressHandlingTarget(

[Mathieu, 2017/03/26 02:03:51]

since it's in the anonymous namespace, a short function comment would be good.

[vabr (Chromium), 2017/03/26 03:25:40]

Done.

+    content::WebContents* web_contents) {
+  content::RenderFrameHost* frame = web_contents->GetFocusedFrame();
+  if (!frame)
+    frame = web_contents->GetMainFrame();
+  content::RenderWidgetHostView* view = frame->GetView();
+  if (!view)
+    return nullptr;

[Mathieu, 2017/03/26 02:03:51]

this is a sure crash on line 50, no?

[vabr (Chromium), 2017/03/26 03:25:40]

For some reason I only saw the view being null during RemoveKeyPressCallback. My
guess is that during some shutdown sequence this might happen.

During the registering phase, there is no good way to handle this gracefully --
if there is no view and hence RenderWidgetHost, then autofill cannot listen to
keys pressed for the suggestions pop-up. That should not happen, and if it does,
we might as well have a crash to highlight it.

+  return view->GetRenderWidgetHost();
+}
+
+}  // namespace
+
 PopupControllerCommon::PopupControllerCommon(
     const gfx::RectF& element_bounds,
     base::i18n::TextDirection text_direction,
     const gfx::NativeView container_view,
     content::WebContents* web_contents)
     : element_bounds_(element_bounds),
       text_direction_(text_direction),
       container_view_(container_view),
       web_contents_(web_contents),
       key_press_event_target_(NULL) {
 }
 PopupControllerCommon::~PopupControllerCommon() {}
 
 void PopupControllerCommon::SetKeyPressCallback(
     content::RenderWidgetHost::KeyPressEventCallback callback) {
   DCHECK(key_press_event_callback_.is_null());
   key_press_event_callback_ = callback;
 }
 
 void PopupControllerCommon::RegisterKeyPressCallback() {
   if (web_contents_ && !key_press_event_target_) {
-    key_press_event_target_ = web_contents_->GetRenderViewHost();
-    key_press_event_target_->GetWidget()->AddKeyPressEventCallback(
+    key_press_event_target_ = KeyPressHandlingTarget(web_contents_);
+    key_press_event_target_->AddKeyPressEventCallback(
         key_press_event_callback_);
   }
 }
 
 void PopupControllerCommon::RemoveKeyPressCallback() {
   if (web_contents_ && (!web_contents_->IsBeingDestroyed()) &&
-      key_press_event_target_ == web_contents_->GetRenderViewHost()) {
-    web_contents_->GetRenderViewHost()
-        ->GetWidget()
-        ->RemoveKeyPressEventCallback(key_press_event_callback_);
+      key_press_event_target_ == KeyPressHandlingTarget(web_contents_)) {
+    key_press_event_target_->RemoveKeyPressEventCallback(
+        key_press_event_callback_);
   }
   key_press_event_target_ = NULL;
 }
 
 }  // namespace autofill