New media playback UI.

Source/core/html/shadow/MediaControlElementTypes.h

Index: Source/core/html/shadow/MediaControlElementTypes.h
diff --git a/Source/core/html/shadow/MediaControlElementTypes.h b/Source/core/html/shadow/MediaControlElementTypes.h
index 09ad25fe82421f4fb91c91483cb4f623a241aef4..872ab1be1b9950169d1fd8d2ff9e674ea37667a5 100644
--- a/Source/core/html/shadow/MediaControlElementTypes.h
+++ b/Source/core/html/shadow/MediaControlElementTypes.h
@@ -78,6 +78,19 @@ class MediaControlElement : public WillBeGarbageCollectedMixin {
 public:
     void hide();
     void show();
+    bool isShown();
+
+    // These hold the state about whether this control should be shown if

[philipj_slow, 2015/07/08 15:06:38]

OK, I take it the problem is that there are now two different reasons that
something can be hidden:
1. Because it makes no sense, e.g. the CC button where there are no captions.
2. Because it won't fit.

Keeping show() and hide() exposed and having want() and dontWant() call those
internally seems like it might invite mistakes, by code calling show() or hide()
directly, and just confusion about how this works.

Could the new model be made explicit by having exposed ways of saying that the
element isn't needed for the two different reasons, and then handling the actual
display state internally based on those two bits?

Alternatively, if there's any way for the elements to not have any knowledge
about the reason they're being shown or hidden, that would also be cleaner, but
I don't know where one would keep track of the state to avoid showing the
element again when just one of the bits flips to the "can show" state.

[liberato (no reviews please), 2015/07/09 12:10:56]

originally, i tried to keep the state in MediaControls, since i prefer for the
elements not to know anything about this.  however, it was fairly cumbersome.

i made fits/doesnt fit properties of the element, and made hide/show private.

+    // space permits.  These will also show / hide as needed, though
+    // calling show/hide does not impact the want/dontWant state.
+    void want();
+    void dontWant();
+    bool isWanted();
+
+    // This returns the minimum width in pixels that we need to show
+    // this control.  Ideally, this would just be shorthand for the css

[philipj_slow, 2015/07/08 15:06:38]

s/css attributes/computed style/

[liberato (no reviews please), 2015/07/09 12:10:56]

Done.

+    // attributes, but this must also work when the control is hidden.
+    int minimumWidth();
 
     MediaControlElementType displayType() { return m_displayType; }
 
@@ -95,6 +108,8 @@ private:
     MediaControls& m_mediaControls;
     MediaControlElementType m_displayType;
     RawPtrWillBeMember<HTMLElement> m_element;
+    bool m_isShown;
+    bool m_isWanted;
 };
 
 // ----------------------------