CC::Animations should use TimeTicks & TimeDelta to represent time

cc/animation/animation.cc

Index: cc/animation/animation.cc
diff --git a/cc/animation/animation.cc b/cc/animation/animation.cc
index be0e29116ee50f77e74b21d2814cde48ca407c47..1154884e32ce984274fc49fd7e358c008d7b4e2d 100644
--- a/cc/animation/animation.cc
+++ b/cc/animation/animation.cc
@@ -9,6 +9,7 @@
 #include "base/debug/trace_event.h"
 #include "base/strings/string_util.h"
 #include "cc/animation/animation_curve.h"
+#include "cc/base/time_util.h"
 
 namespace {
 
@@ -64,14 +65,14 @@ Animation::Animation(scoped_ptr<AnimationCurve> curve,
       target_property_(target_property),
       run_state_(WaitingForTargetAvailability),
       iterations_(1),
-      start_time_(0),
+      start_time_(),
       direction_(Normal),
-      time_offset_(0),
+      time_offset_(),
       needs_synchronized_start_time_(false),
       received_finished_event_(false),
       suspended_(false),
-      pause_time_(0),
-      total_paused_time_(0),
+      pause_time_(),
+      total_paused_time_(),
       is_controlling_instance_(false),
       is_impl_only_(false),
       affects_active_observers_(true),
@@ -80,10 +81,11 @@ Animation::Animation(scoped_ptr<AnimationCurve> curve,
 
 Animation::~Animation() {
   if (run_state_ == Running || run_state_ == Paused)
-    SetRunState(Aborted, 0);
+    SetRunState(Aborted, base::TimeTicks());
 }
 
-void Animation::SetRunState(RunState run_state, double monotonic_time) {
+void Animation::SetRunState(RunState run_state,
+                            base::TimeTicks monotonic_time) {
   if (suspended_)
     return;
 
@@ -108,7 +110,7 @@ void Animation::SetRunState(RunState run_state, double monotonic_time) {
   const char* old_run_state_name = s_runStateNames[run_state_];
 
   if (run_state == Running && run_state_ == Paused)
-    total_paused_time_ += monotonic_time - pause_time_;
+    total_paused_time_ += (monotonic_time - pause_time_);
   else if (run_state == Paused)
     pause_time_ = monotonic_time;
   run_state_ = run_state;
@@ -134,47 +136,50 @@ void Animation::SetRunState(RunState run_state, double monotonic_time) {
                        TRACE_STR_COPY(state_buffer));
 }
 
-void Animation::Suspend(double monotonic_time) {
+void Animation::Suspend(base::TimeTicks monotonic_time) {
   SetRunState(Paused, monotonic_time);
   suspended_ = true;
 }
 
-void Animation::Resume(double monotonic_time) {
+void Animation::Resume(base::TimeTicks monotonic_time) {
   suspended_ = false;
   SetRunState(Running, monotonic_time);
 }
 
-bool Animation::IsFinishedAt(double monotonic_time) const {
+bool Animation::IsFinishedAt(base::TimeTicks monotonic_time) const {
   if (is_finished())
     return true;
 
   if (needs_synchronized_start_time_)
     return false;
 
-  return run_state_ == Running &&
-         iterations_ >= 0 &&
-         iterations_ * curve_->Duration() <= (monotonic_time -
-                                              start_time() -
-                                              total_paused_time_ +
-                                              time_offset_);
+  return run_state_ == Running && iterations_ >= 0 &&
+         iterations_ * curve_->Duration() <=
+             (TimeUtil::TicksInSecondsF(monotonic_time) +
+              time_offset_.InSecondsF() -
+              TimeUtil::TicksInSecondsF(start_time_) -
+              total_paused_time_.InSecondsF());
 }
 
-double Animation::TrimTimeToCurrentIteration(double monotonic_time) const {
-  double trimmed = monotonic_time + time_offset_;
+double Animation::TrimTimeToCurrentIteration(
+    base::TimeTicks monotonic_time) const {
+  double trimmed =
+      TimeUtil::TicksInSecondsF(monotonic_time) + time_offset_.InSecondsF();
 
   // If we're paused, time is 'stuck' at the pause time.
   if (run_state_ == Paused)
-    trimmed = pause_time_;
+    trimmed = TimeUtil::TicksInSecondsF(pause_time_);
 
   // Returned time should always be relative to the start time and should
   // subtract all time spent paused.
-  trimmed -= start_time_ + total_paused_time_;
+  trimmed -=
+      TimeUtil::TicksInSecondsF(start_time_) + total_paused_time_.InSecondsF();
 
   // If we're just starting or we're waiting on receiving a start time,
   // time is 'stuck' at the initial state.
   if ((run_state_ == Starting && !has_set_start_time()) ||
       needs_synchronized_start_time())
-    trimmed = time_offset_;
+    trimmed = time_offset_.InSecondsF();
 
   // Return 0 if we are before the start of the animation
   if (trimmed < 0)