New media playback UI.

LayoutTests/TestExpectations

 crbug.com/504613 paint/images/image-backgrounds-not-antialiased.html [ ImageOnlyFailure ]
 crbug.com/502531 fast/borders/border-antialiasing.html [ ImageOnlyFailure ]
 
 crbug.com/474117 compositing/overflow/overflow-positioning.html [ ImageOnlyFailure Pass ]
 
 crbug.com/487281 [ Mac ] fast/forms/menulist-narrow-width.html [ ImageOnlyFailure ]
 
 crbug.com/499688 virtual/rootlayerscrolls/fast/scrolling/background-paint-scrolled.html [ Pass Crash ]
 
 crbug.com/427606 virtual/gpu/fast/canvas/canvas-shadow-source-in.html [ Pass ImageOnlyFailure NeedsManualRebaseline ]
@@ skipping 1483 matching lines @@
 crbug.com/492511 [ Mac ] fast/text/atsui-negative-spacing-features.html [ ImageOnlyFailure ]
 crbug.com/492511 [ Mac ] fast/text/atsui-spacing-features.html [ ImageOnlyFailure ]
 crbug.com/492511 [ Mac ] fast/text/vertical-rl-rtl-linebreak.html [ ImageOnlyFailure NeedsManualRebaseline ]
 crbug.com/492511 [ Mac ] fast/text/international/arabic-justify.html [ ImageOnlyFailure ]
 
 # Temporary, until [Unforgeable] attributes have the right accessors 'get' and 'set'.
 crbug.com/491006 http/tests/security/cross-origin-access-over-property-descriptor.html [ Failure ]
 
 crbug.com/493815 inspector/elements/iframe-load-event.html [ Pass Failure ]
 
+crbug.com/446350 compositing/geometry/video-fixed-scrolling.html [ NeedsRebaseline ]

[philipj_slow, 2015/08/05 08:41:05]

So I ran this test and the failure is:

---
/home/philip/src/chromium/src/webkit/Debug/layout-test-results/compositing/geometry/video-fixed-scrolling-expected.txt
+++
/home/philip/src/chromium/src/webkit/Debug/layout-test-results/compositing/geometry/video-fixed-scrolling-actual.txt
@@ -8,13 +8,15 @@
       LayoutBlockFlow {P} at (0,401) size 769x20
         LayoutText {#text} at (0,0) size 425x19
           text run at (0,0) width 425: "The blue bar should be in front of the
video, and at the top of the page."
+      LayoutBlockFlow (anonymous) at (0,437) size 769x0
+        LayoutText {#text} at (0,0) size 0x0
 layer at (8,88) size 400x300
   LayoutVideo {VIDEO} at (0,80) size 400x300
 layer at (8,88) size 400x300
   LayoutFlexibleBox (relative positioned) {DIV} at (0,0) size 400x300
-    LayoutBlockFlow {DIV} at (0,265) size 400x35
-layer at (8,88) size 400x265
-  LayoutFlexibleBox (relative positioned) {DIV} at (0,0) size 400x265
+    LayoutBlockFlow {DIV} at (0,252) size 400x48
+layer at (8,88) size 400x242
+  LayoutFlexibleBox (relative positioned) {DIV} at (0,0) size 400x242
 layer at (0,50) size 500x60
   LayoutBlockFlow (positioned) {DIV} at (0,0) size 500x60 [bgcolor=#0000FFCC]
 scrolled to 0,50

What is this change, and why is it happening before the flag is flipped?

[liberato (no reviews please), 2015/08/05 16:36:40]

hrm, this is not what i get.  the LayoutBlockFlow with height 48 looks like the
controls were still enabled when this test is run.  when i run them off, i see
only the first two added lines in the diff (LayoutBlockFlow 769x0 and LayoutText
0x0).

The x0 lines show up with the call to clientWidth() at the end of
MediaControls::reset() to set m_panelWidth.  I'll make it conditional on the
flag, then the test passes.

i have absolutely no idea why asking for the width causes the render tree to
change.  i added a comment in reset() that describes it.

+
 crbug.com/493939 [ XP ] http/tests/security/cross-origin-css.html [ Timeout Pass ]
 
 crbug.com/321237 [ Mac ] fast/text/international/bidi-neutral-run.html [ Pass Crash NeedsManualRebaseline ]
 
 # Ref tests that fail due to differences in inline box structure, even though they contain the same text.
 # This happens because inline box layout uses fixed-point measurements, which can cause rounding differences.
 crbug.com/321237 [ Mac ] fast/dom/shadow/shadow-insertion-point-rendering-multiple-shadow-roots.html [ ImageOnlyFailure ]
 crbug.com/321237 [ Mac ] fast/selectors/007a.html [ ImageOnlyFailure ]
 crbug.com/321237 [ Mac Win ] fast/text-autosizing/inherited-multiplier.html [ ImageOnlyFailure ]
 crbug.com/321237 [ Mac ] virtual/stable/fast/css3-text/css3-text-decoration/stable/first-letter-text-decoration.html [ ImageOnlyFailure ]
@@ skipping 1327 matching lines @@
 
 crbug.com/512709 [ XP ] fast/text/emphasis.html [ Pass ImageOnlyFailure ]
 
 crbug.com/513073 [ Win ] http/tests/inspector/network/long-script-content.html [ Pass Timeout ]
 crbug.com/513073 [ Win ] http/tests/inspector/network/network-disable-cache-memory.html [ Pass Timeout ]
 crbug.com/513073 [ Win ] http/tests/inspector/extensions-ignore-cache.html [ Pass Timeout ]
 crbug.com/513073 [ Win ] http/tests/inspector/network/network-memory-cached-resource.html [ Pass Timeout ]
 
 crbug.com/502927 [ XP ] paint/frames/frameset-with-stacking-context-and-not-stacking-context-children.html [ Failure ]
 crbug.com/502927 [ XP ] paint/frames/frameset-with-stacking-contexts.html [ Failure ]