Hide overlay play button if it can't be shown without clipping

third_party/WebKit/Source/core/layout/LayoutMedia.cpp

 /*
  * Copyright (C) 2007, 2008, 2009, 2010 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 36 matching lines @@
 
 void LayoutMedia::layout() {
   LayoutSize oldSize = contentBoxRect().size();
 
   LayoutImage::layout();
 
   LayoutRect newRect = contentBoxRect();
 
   LayoutState state(*this);
 
-  Optional<LayoutUnit> newPanelWidth;
-
 // Iterate the children in reverse order so that the media controls are laid
 // out before the text track container. This is to ensure that the text
 // track rendering has an up-to-date position of the media controls for
 // overlap checking, see LayoutVTTCue.
 #if DCHECK_IS_ON()
   bool seenTextTrackContainer = false;
 #endif
   for (LayoutObject* child = m_children.lastChild(); child;
        child = child->previousSibling()) {
 #if DCHECK_IS_ON()
     if (child->node()->isMediaControls())
       ASSERT(!seenTextTrackContainer);
     else if (child->node()->isTextTrackContainer())
       seenTextTrackContainer = true;
     else
       ASSERT_NOT_REACHED();
 #endif
 
     // TODO(mlamouri): we miss some layouts because needsLayout returns false in
     // some cases where we want to change the width of the controls because the
     // visible viewport has changed for example.
     if (newRect.size() == oldSize && !child->needsLayout())
       continue;
 
     LayoutUnit width = newRect.width();
     if (child->node()->isMediaControls()) {
       width = computePanelWidth(newRect);
-      newPanelWidth = width;

[mlamouri (slow - plz ping), 2017/03/07 19:07:30]

Here, we set `width` then pass it to `newPanelWidth` which was then sent to the
MediaControls. My intuition is that `computePanelWidth()` became irrelevant.
Should this logic be moved to the HTMLMediaControls then?

[mlamouri (slow - plz ping), 2017/03/08 19:13:04]

Scratch that comment :)

[steimel, 2017/03/09 16:42:24]

Acknowledged.

     }
 
     LayoutBox* layoutBox = toLayoutBox(child);
     layoutBox->setLocation(newRect.location());
     // TODO(foolip): Remove the mutableStyleRef() and depend on CSS
     // width/height: inherit to match the media element size.
     layoutBox->mutableStyleRef().setHeight(Length(newRect.height(), Fixed));
     layoutBox->mutableStyleRef().setWidth(Length(width, Fixed));
 
     layoutBox->forceLayout();
   }
 
   clearNeedsLayout();
-
-  // Notify our MediaControls that a layout has happened.
-  if (mediaElement() && mediaElement()->mediaControls() &&
-      newPanelWidth.has_value()) {
-    if (!m_lastReportedPanelWidth.has_value() ||
-        m_lastReportedPanelWidth.value() != newPanelWidth.value()) {
-      mediaElement()->mediaControls()->notifyPanelWidthChanged(
-          newPanelWidth.value());
-      // Store the last value we reported, so we know if it has changed.
-      m_lastReportedPanelWidth = newPanelWidth.value();
-    }
-  }
 }
 
 bool LayoutMedia::isChildAllowed(LayoutObject* child,
                                  const ComputedStyle& style) const {
   // Two types of child layout objects are allowed: media controls
   // and the text track container. Filter children by node type.
   ASSERT(child->node());
 
   // Out-of-flow positioned or floating child breaks layout hierarchy.
   // This check can be removed if ::-webkit-media-controls is made internal.
@@ skipping 47 matching lines @@
           .x());
   const LayoutUnit newWidth = visibleWidth - absoluteXOffset;
 
   if (newWidth < 0)
     return mediaRect.width();
 
   return std::min(mediaRect.width(), visibleWidth - absoluteXOffset);
 }
 
 }  // namespace blink