Hide separators on ends when tab shapes are visible.

Bug: 862438
Change-Id: I51e0b61d14184e0f94467bc957240091d77897f3
Reviewed-on: https://chromium-review.googlesource.com/1173755
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Reviewed-by: Bret Sepulveda <bsep@chromium.org>
Cr-Commit-Position: refs/heads/master@{#584263}

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

@@ -386,6 +386,11 @@ void BrowserTabStripController::OnStoppedDraggingTabs() {
   immersive_reveal_lock_.reset();
 }
 
+bool BrowserTabStripController::HasVisibleBackgroundTabShapes() const {
+  return GetFrameView()->HasVisibleBackgroundTabShapes(
+      BrowserNonClientFrameView::kUseCurrent);
+}
+
 bool BrowserTabStripController::EverHasVisibleBackgroundTabShapes() const {
   return GetFrameView()->EverHasVisibleBackgroundTabShapes();
 }

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

@@ -76,6 +76,7 @@ class BrowserTabStripController : public TabStripController,
   bool ShouldDrawStrokes() const override;
   void OnStartedDraggingTabs() override;
   void OnStoppedDraggingTabs() override;
+  bool HasVisibleBackgroundTabShapes() const override;
   bool EverHasVisibleBackgroundTabShapes() const override;
   SkColor GetFrameColor() const override;
   SkColor GetToolbarTopSeparatorColor() const override;

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

@@ -150,6 +150,10 @@ void FakeBaseTabStripController::OnStartedDraggingTabs() {
 void FakeBaseTabStripController::OnStoppedDraggingTabs() {
 }
 
+bool FakeBaseTabStripController::HasVisibleBackgroundTabShapes() const {
+  return false;
+}
+
 bool FakeBaseTabStripController::EverHasVisibleBackgroundTabShapes() const {
   return false;
 }

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

@@ -52,6 +52,7 @@ class FakeBaseTabStripController : public TabStripController {
   bool ShouldDrawStrokes() const override;
   void OnStartedDraggingTabs() override;
   void OnStoppedDraggingTabs() override;
+  bool HasVisibleBackgroundTabShapes() const override;
   bool EverHasVisibleBackgroundTabShapes() const override;
   SkColor GetFrameColor() const override;
   SkColor GetToolbarTopSeparatorColor() const override;

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

@@ -1678,9 +1678,14 @@ Tab::SeparatorOpacities Tab::GetSeparatorOpacities(bool for_layout) const {
   const int tab_width = std::max(width(), target_bounds.width());
   const float target_opacity =
       float{std::min(std::abs(x() - target_bounds.x()), tab_width)} / tab_width;
-  if (ntb_position != LEADING && controller_->IsFirstVisibleTab(this))
+  // If the tab shapes are visible, never draw end separators.
+  const bool always_hide_separators_on_ends =
+      controller_->HasVisibleBackgroundTabShapes();
+  if (controller_->IsFirstVisibleTab(this) &&
+      (ntb_position != LEADING || always_hide_separators_on_ends))
     leading_opacity = target_opacity;
-  if (ntb_position != AFTER_TABS && controller_->IsLastVisibleTab(this))
+  if (controller_->IsLastVisibleTab(this) &&
+      (ntb_position != AFTER_TABS || always_hide_separators_on_ends))
     trailing_opacity = target_opacity;
 
   // Return the opacities in physical order, rather than logical.

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

@@ -142,6 +142,10 @@ class TabController {
   // in the same window will redraw on top of the the favicon area of any tab.
   virtual bool CanPaintThrobberToLayer() const = 0;
 
+  // Returns whether the shapes of background tabs are visible against the
+  // frame.
+  virtual bool HasVisibleBackgroundTabShapes() const = 0;
+
   // Returns COLOR_TOOLBAR_TOP_SEPARATOR[,_INACTIVE] depending on the activation
   // state of the window.
   virtual SkColor GetToolbarTopSeparatorColor() const = 0;

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

@@ -1139,6 +1139,10 @@ bool TabStrip::CanPaintThrobberToLayer() const {
          !widget->IsFullscreen();
 }
 
+bool TabStrip::HasVisibleBackgroundTabShapes() const {
+  return controller_->HasVisibleBackgroundTabShapes();
+}
+
 SkColor TabStrip::GetToolbarTopSeparatorColor() const {
   return controller_->GetToolbarTopSeparatorColor();
 }

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

@@ -256,6 +256,7 @@ class TabStrip : public views::View,
       gfx::Path* clip) override;
   int GetStrokeThickness() const override;
   bool CanPaintThrobberToLayer() const override;
+  bool HasVisibleBackgroundTabShapes() const override;
   SkColor GetToolbarTopSeparatorColor() const override;
   SkColor GetTabSeparatorColor() const override;
   SkColor GetTabBackgroundColor(TabState state, bool opaque) const override;

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

@@ -120,6 +120,10 @@ class TabStripController {
   // from this tabstrip but the user is still dragging the tabs.
   virtual void OnStoppedDraggingTabs() = 0;
 
+  // Returns whether the shapes of background tabs are visible against the
+  // frame.
+  virtual bool HasVisibleBackgroundTabShapes() const = 0;
+
   // Returns whether the shapes of background tabs are visible against the
   // frame for either active or inactive windows.
   virtual bool EverHasVisibleBackgroundTabShapes() const = 0;

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

@@ -86,6 +86,7 @@ class FakeTabController : public TabController {
   bool CanPaintThrobberToLayer() const override {
     return paint_throbber_to_layer_;
   }
+  bool HasVisibleBackgroundTabShapes() const override { return false; }
   SkColor GetToolbarTopSeparatorColor() const override { return SK_ColorBLACK; }
   SkColor GetTabSeparatorColor() const override { return SK_ColorBLACK; }
   SkColor GetTabBackgroundColor(TabState state, bool opaque) const override {