cc: Refactoring of HudLayer contents and UI polishing

This change refactors drawing and updating of HudLayer contents and introduces small UI improvements.

Refactoring:
- Made all drawing methods const.
- HeadsUpDisplayLayerImpl::updateHudContents() manages graph value updating now.
- Widget drawing methods return the area the widget covers.
- Debug rectangle drawing reuses one SkPaint instance.
- Added all colors to DebugColors.
- Turned Graph helper structure into a class.

UI changes:
- Synced memory stats updating with graph value updating and increased font size to improve readability.
- Memory stats display gets flexible width to adapt to the widget previously drawn.
- Removed the 1px gaps in the paint time graph to display more values and increased size of the paint time counter buffer.
- Indicator line in the graph is drawn on top of paint time graph and uses additive blending to increase contrast.
- Increased saturation of the paint time counter's green.
- Removed the 2px top/left offset from the border for widgets.
- New drawing order: debug rectangles, platform layer tree, FPS counter | paint time counter, memory stats;

Screenshot: https://docs.google.com/file/d/0B8Y78t3tjy1XdXYzelVRdGVnQzg/edit?usp=sharing

BUG=


Review URL: https://chromiumcodereview.appspot.com/12468003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@186495 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 1 insertions, 0 deletions

diff --git a/cc/layer_tree_debug_state.h b/cc/layer_tree_debug_state.h
index 0931908..e488558 100644
--- a/cc/layer_tree_debug_state.h
+++ b/cc/layer_tree_debug_state.h
@@ -36,6 +36,7 @@ class CC_EXPORT LayerTreeDebugState {
 
   bool showHudInfo() const;
   bool showHudRects() const;
+  bool showMemoryStats() const;
 
   static bool equal(const LayerTreeDebugState& a, const LayerTreeDebugState& b);
   static LayerTreeDebugState unite(const LayerTreeDebugState& a, const LayerTreeDebugState& b);