VR: Revert controller timestamp adjustment

Recently we replaced the controller event timestamps with timestamps
generated by the VR Controller. However, these timestamps aren't in the
same timebase, and so cannot be used.

Bug: 732830
Change-Id: I33cb642e0008eb1676a65596c83e3982fe5a59f6
Reviewed-on: https://chromium-review.googlesource.com/568687Reviewed-by: Amirhossein Simjour <asimjour@chromium.org>
Commit-Queue: Michael Thiessen <mthiesse@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487231}

chrome/browser/android/vr_shell/vr_controller.cc

@@ -48,8 +48,6 @@ constexpr int kMaxNumOfExtrapolations = 2;
 // Distance from the center of the controller to start rendering the laser.
 constexpr float kLaserStartDisplacement = 0.045;
 
-constexpr int microsPerNano = 1000;
-
 void ClampTouchpadPosition(gfx::Vector2dF* position) {
   position->set_x(cc::MathUtil::ClampToRange(position->x(), 0.0f, 1.0f));
   position->set_y(cc::MathUtil::ClampToRange(position->y(), 0.0f, 1.0f));
@@ -146,18 +144,24 @@ float VrController::TouchPosY() {
 }
 
 base::TimeTicks VrController::GetLastOrientationTimestamp() const {
-  return base::TimeTicks::FromInternalValue(
-      controller_state_->GetLastOrientationTimestamp() / microsPerNano);
+  // controller_state_->GetLast*Timestamp() returns timestamps in a
+  // different timebase from base::TimeTicks::Now(), so we can't use the
+  // timestamps in any meaningful way in the rest of Chrome.
+  // TODO(mthiesse): Use controller_state_->GetLastOrientationTimestamp() when
+  // b/62818778 is resolved.
+  return base::TimeTicks::Now();
 }
 
 base::TimeTicks VrController::GetLastTouchTimestamp() const {
-  return base::TimeTicks::FromInternalValue(
-      controller_state_->GetLastTouchTimestamp() / microsPerNano);
+  // TODO(mthiesse): Use controller_state_->GetLastTouchTimestamp() when
+  // b/62818778 is resolved.
+  return base::TimeTicks::Now();
 }
 
 base::TimeTicks VrController::GetLastButtonTimestamp() const {
-  return base::TimeTicks::FromInternalValue(
-      controller_state_->GetLastButtonTimestamp() / microsPerNano);
+  // TODO(mthiesse): Use controller_state_->GetLastButtonTimestamp() when
+  // b/62818778 is resolved.
+  return base::TimeTicks::Now();
 }
 
 gfx::Quaternion VrController::Orientation() const {