Add Color animation curves.

Implement animation curves for colors.

This is the first step towards accelerating background-color animations.

+ Add ColorValueBetween to gfx::Tween.
+ Add test/color_utils which gives EXPECT_COLOR_EQ to check SkColors and
  print in a sane format.
~ Fixed discrepancy between two methods of interpolating ints.
~ Factored out GetProgress into template function to simplify code in
  the implementations of GetValue(double), there was a lot of duplication
  there.

TESTED:
  Added tests for the new KeyframedColorAnimations and AnimatedColor classes. Added tests to tweening.

R=ajuma
BUG=290234

Review URL: https://codereview.chromium.org/25901002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230856 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 7 insertions, 0 deletions

diff --git a/cc/animation/animation_curve.cc b/cc/animation/animation_curve.cc
index cf04da7..65c21db 100644
--- a/cc/animation/animation_curve.cc
+++ b/cc/animation/animation_curve.cc
@@ -8,6 +8,13 @@
 
 namespace cc {
 
+const ColorAnimationCurve* AnimationCurve::ToColorAnimationCurve() const {
+  DCHECK(Type() == AnimationCurve::Color);
+  return static_cast<const ColorAnimationCurve*>(this);
+}
+
+AnimationCurve::CurveType ColorAnimationCurve::Type() const { return Color; }
+
 const FloatAnimationCurve* AnimationCurve::ToFloatAnimationCurve() const {
   DCHECK(Type() == AnimationCurve::Float);
   return static_cast<const FloatAnimationCurve*>(this);