cc: Make PictureLayerImpl use a better choice for animated raster scale.

cc/animation/keyframed_animation_curve.cc

Index: cc/animation/keyframed_animation_curve.cc
diff --git a/cc/animation/keyframed_animation_curve.cc b/cc/animation/keyframed_animation_curve.cc
index bcf067ebb74b1f79a7416b33fd7f6f9070271f24..7869d2f48995dfa0361849192a6b1a202ee2ee86 100644
--- a/cc/animation/keyframed_animation_curve.cc
+++ b/cc/animation/keyframed_animation_curve.cc
@@ -366,7 +366,8 @@ bool KeyframedTransformAnimationCurve::IsTranslation() const {
   return true;
 }
 
-bool KeyframedTransformAnimationCurve::MaximumScale(float* max_scale) const {
+bool KeyframedTransformAnimationCurve::MaximumTargetScale(
+    float* max_scale) const {
   DCHECK_GE(keyframes_.size(), 2ul);
   *max_scale = 0.f;
   for (size_t i = 1; i < keyframes_.size(); ++i) {
@@ -375,14 +376,14 @@ bool KeyframedTransformAnimationCurve::MaximumScale(float* max_scale) const {
     if (keyframes_[i - 1]->timing_function())
       keyframes_[i - 1]->timing_function()->Range(&min_progress, &max_progress);
 
-    float max_scale_for_segment = 0.f;
-    if (!keyframes_[i]->Value().MaximumScale(keyframes_[i - 1]->Value(),
-                                             min_progress,
-                                             max_progress,
-                                             &max_scale_for_segment))
+    gfx::Vector3dF target_scale_for_segment;
+    if (!keyframes_[i]->Value().ScaleComponent(&target_scale_for_segment))
       return false;
-
-    *max_scale = std::max(*max_scale, max_scale_for_segment);
+    float max_scale_for_segment =
+        fmax(std::abs(target_scale_for_segment.x()),
+             fmax(std::abs(target_scale_for_segment.y()),
+                  std::abs(target_scale_for_segment.z())));
+    *max_scale = fmax(*max_scale, max_scale_for_segment);
   }
   return true;
 }