Animation start scale should be considered for the raster scale

cc/animation/keyframed_animation_curve.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <algorithm>
 
 #include "cc/animation/keyframed_animation_curve.h"
 #include "cc/base/time_util.h"
 #include "ui/gfx/animation/tween.h"
 #include "ui/gfx/geometry/box_f.h"
@@ skipping 361 matching lines @@
 }
 
 bool KeyframedTransformAnimationCurve::IsTranslation() const {
   for (size_t i = 0; i < keyframes_.size(); ++i) {
     if (!keyframes_[i]->Value().IsTranslation() &&
         !keyframes_[i]->Value().IsIdentity())
       return false;
   }
   return true;
 }
+bool KeyframedTransformAnimationCurve::AnimationStartScale(
+    bool forward_direction,
+    float* start_scale) const {
+  DCHECK_GE(keyframes_.size(), 2ul);
+  *start_scale = 0.f;
+  size_t start_location = 0;
+  if (!forward_direction) {
+    start_location = keyframes_.size() - 1;
+  }
 
+  gfx::Vector3dF initial_target_scale;
+  if (!keyframes_[start_location]->Value().ScaleComponent(
+          &initial_target_scale))
+    return false;
+  float start_scale_for_segment =
+      fmax(std::abs(initial_target_scale.x()),
+           fmax(std::abs(initial_target_scale.y()),
+                std::abs(initial_target_scale.z())));
+  *start_scale = start_scale_for_segment;
+  return true;
+}
 bool KeyframedTransformAnimationCurve::MaximumTargetScale(
     bool forward_direction,
     float* max_scale) const {
   DCHECK_GE(keyframes_.size(), 2ul);
   *max_scale = 0.f;
 
   // If |forward_direction| is true, then skip the first frame, otherwise
   // skip the last frame, since that is the original position in the animation.
   size_t start = 1;
   size_t end = keyframes_.size();
@@ skipping 63 matching lines @@
 bool KeyframedFilterAnimationCurve::HasFilterThatMovesPixels() const {
   for (size_t i = 0; i < keyframes_.size(); ++i) {
     if (keyframes_[i]->Value().HasFilterThatMovesPixels()) {
       return true;
     }
   }
   return false;
 }
 
 }  // namespace cc