Implement tab insertion animation in new style.

Bug: 958173
Change-Id: I99cd5c3ed9e2326db14a8e8d225b565aaac82ea7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1639731
Commit-Queue: Taylor Bergquist <tbergquist@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666387}

chrome/browser/ui/views/tabs/tab_strip.cc

@@ -1001,14 +1001,14 @@ void TabStrip::AddTabAt(int model_index, TabRendererData data, bool is_active) {
   TabAnimationState::TabPinnedness pinnedness =
       pinned ? TabAnimationState::TabPinnedness::kPinned
              : TabAnimationState::TabPinnedness::kUnpinned;
+  if (tab_count() > 1 && GetWidget() && GetWidget()->IsVisible()) {
+    StartInsertTabAnimation(model_index, activeness, pinnedness);
+  } else {
     animator_->InsertTabAtNoAnimation(
         model_index,
         base::BindOnce(&TabStrip::OnTabCloseAnimationCompleted,
                        base::Unretained(this), base::Unretained(tab)),
         activeness, pinnedness);
-  if (tab_count() > 1 && GetWidget() && GetWidget()->IsVisible()) {
-    StartInsertTabAnimation(model_index);
-  } else {
     CompleteAnimationAndLayout();
   }
 
@@ -2081,7 +2081,27 @@ void TabStrip::Init() {
     bounds_animator_.SetAnimationDuration(0);
 }
 
-void TabStrip::StartInsertTabAnimation(int model_index) {
+void TabStrip::StartInsertTabAnimation(
+    int model_index,
+    TabAnimationState::TabActiveness activeness,
+    TabAnimationState::TabPinnedness pinnedness) {
+  if (!bounds_animator_.IsAnimating() && !in_tab_close_) {
+    animator_->InsertTabAt(
+        model_index,
+        base::BindOnce(&TabStrip::OnTabCloseAnimationCompleted,
+                       base::Unretained(this),
+                       base::Unretained(tab_at(model_index))),
+        activeness, pinnedness);
+  } else {
+    // TODO(958173): Delete this branch once |animator_| has taken over all
+    // animation responsibilities.
+    animator_->InsertTabAtNoAnimation(
+        model_index,
+        base::BindOnce(&TabStrip::OnTabCloseAnimationCompleted,
+                       base::Unretained(this),
+                       base::Unretained(tab_at(model_index))),
+        activeness, pinnedness);
+
     PrepareForAnimation();
 
     // The TabStrip can now use its entire width to lay out Tabs.
@@ -2097,14 +2117,15 @@ void TabStrip::StartInsertTabAnimation(int model_index) {
     if (model_index > 0)
       bounds.set_x(tab_at(model_index - 1)->bounds().right() - tab_overlap);
 
-  // Start at the width of the overlap in order to animate at the same speed the
-  // surrounding tabs are moving, since at this width the subsequent tab is
-  // naturally positioned at the same X coordinate.
+    // Start at the width of the overlap in order to animate at the same speed
+    // the surrounding tabs are moving, since at this width the subsequent tab
+    // is naturally positioned at the same X coordinate.
     bounds.set_width(tab_overlap);
 
     // Animate in to the full width.
     tab_at(model_index)->SetBoundsRect(bounds);
     AnimateToIdealBounds();
+  }
 }
 
 void TabStrip::StartMoveTabAnimation() {

chrome/browser/ui/views/tabs/tab_strip.h

@@ -336,7 +336,9 @@ class TabStrip : public views::AccessiblePaneView,
   void Init();
 
   // Invoked from |AddTabAt| after the newly created tab has been inserted.
-  void StartInsertTabAnimation(int model_index);
+  void StartInsertTabAnimation(int model_index,
+                               TabAnimationState::TabActiveness activeness,
+                               TabAnimationState::TabPinnedness pinnedness);
 
   // Invoked from |MoveTab| after |tab_data_| has been updated to animate the
   // move.

chrome/browser/ui/views/tabs/tab_strip_animator.cc

@@ -81,18 +81,16 @@ void TabStripAnimator::RemoveTab(int index) {
 
 void TabStripAnimator::SetActiveTab(int prev_active_index,
                                     int new_active_index) {
-  // Set activeness without animating by immediately completing animations.
+  // Set activeness without animating by retargeting the existing animation.
   if (prev_active_index >= 0) {
-    animations_[prev_active_index].AnimateTo(
+    animations_[prev_active_index].RetargetTo(
         animations_[prev_active_index].target_state().WithActiveness(
             TabAnimationState::TabActiveness::kInactive));
-    animations_[prev_active_index].CompleteAnimation();
   }
   if (new_active_index >= 0) {
-    animations_[new_active_index].AnimateTo(
+    animations_[new_active_index].RetargetTo(
         animations_[new_active_index].target_state().WithActiveness(
             TabAnimationState::TabActiveness::kActive));
-    animations_[new_active_index].CompleteAnimation();
   }
 }
 

chrome/browser/ui/views/tabs/tab_strip_unittest.cc

@@ -794,8 +794,11 @@ TEST_P(TabStripTest, ActiveTabWidthWhenTabsAreTiny) {
 
   // Create a lot of tabs in order to make inactive tabs tiny.
   const int min_inactive_width = TabStyleViews::GetMinimumInactiveWidth();
-  while (GetInactiveTabWidth() != min_inactive_width)
+  while (GetInactiveTabWidth() != min_inactive_width) {
     controller_->CreateNewTab();
+    CompleteAnimationAndLayout();
+  }
+
   EXPECT_GT(tab_strip_->tab_count(), 1);
 
   const int active_index = controller_->GetActiveIndex();
@@ -826,6 +829,7 @@ TEST_P(TabStripTest, InactiveTabWidthWhenTabsAreTiny) {
   const int min_active_width = TabStyleViews::GetMinimumActiveWidth();
   while (GetInactiveTabWidth() >= (min_inactive_width + min_active_width) / 2) {
     controller_->CreateNewTab();
+    CompleteAnimationAndLayout();
   }
 
   // During mouse-based tab closure, inactive tabs shouldn't shrink

chrome/browser/ui/views/tabs/tab_style_views.cc

@@ -612,7 +612,8 @@ float GM2TabStyle::GetHoverOpacity() const {
   const float range_start = float{GetStandardWidth()};
   const float range_end = float{GetMinimumInactiveWidth()};
   const float value_in_range = float{tab_->width()};
-  const float t = (value_in_range - range_start) / (range_end - range_start);
+  const float t = base::ClampToRange(
+      (value_in_range - range_start) / (range_end - range_start), 0.0f, 1.0f);
   return tab_->controller()->GetHoverOpacityForTab(t * t);
 }