Changing URL bar constraints only calls performResize on Hidden <-> Both

third_party/WebKit/Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1780 matching lines @@
 }
 
 void WebViewImpl::updateBrowserControlsState(WebBrowserControlsState constraint,
                                              WebBrowserControlsState current,
                                              bool animate) {
   WebBrowserControlsState oldPermittedState =
       browserControls().permittedState();
 
   browserControls().updateConstraintsAndState(constraint, current, animate);
 
-  // If the controls are going from a locked to an unlocked state, or
-  // vice-versa, then we need to force a recompute of the ICB size since that
-  // depends on the permitted browser controls state.
-  if (oldPermittedState != constraint &&
-      (oldPermittedState == WebBrowserControlsBoth ||
-       constraint == WebBrowserControlsBoth)) {
+  // If the controls are going from a locked hidden to unlocked state, or vice
+  // versa, the ICB size needs to change but we can't rely on getting a
+  // WebViewImpl::resize since the top controls shown state may not have
+  // changed.
+  if ((oldPermittedState == WebBrowserControlsHidden &&
+       constraint == WebBrowserControlsBoth) ||
+      (oldPermittedState == WebBrowserControlsBoth &&
+       constraint == WebBrowserControlsHidden)) {
     performResize();
   }
 
   if (m_layerTreeView)
     m_layerTreeView->updateBrowserControlsState(constraint, current, animate);
 }
 
 void WebViewImpl::didUpdateBrowserControls() {
   if (m_layerTreeView) {
     m_layerTreeView->setBrowserControlsShownRatio(
@@ skipping 2369 matching lines @@
   if (focusedFrame->localFrameRoot() != mainFrameImpl()->frame())
     return nullptr;
   return focusedFrame;
 }
 
 LocalFrame* WebViewImpl::focusedLocalFrameAvailableForIme() const {
   return m_imeAcceptEvents ? focusedLocalFrameInWidget() : nullptr;
 }
 
 }  // namespace blink