[Mac] Stop tabs dragged out of a fullscreen window from immediately entering fullscreen.

- Adds Widget::SetFullscreenAuxiliary(), which sets
  NSWindowCollectionBehaviorFullScreenAuxiliary and lets the dragging
  window exist in another window's fullscreen space.

- Sets that flag when tab dragging starts, clears it when dragging ends, and
  makes the new window fullscreen if the source was fullscreen.

Bug: 883910
Change-Id: I8889135320a0fb26abff9b546c5f5444ba6f4486
Reviewed-on: https://chromium-review.googlesource.com/c/1484491
Commit-Queue: Sidney San Martín <sdy@chromium.org>
Auto-Submit: Sidney San Martín <sdy@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#636278}

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

@@ -1282,6 +1282,7 @@ void TabDragController::DetachIntoNewBrowserAndRunMoveLoop(
 
   Detach(can_release_capture_ ? RELEASE_CAPTURE : DONT_RELEASE_CAPTURE);
 
+  dragged_widget->SetCanAppearInExistingFullscreenSpaces(true);
   dragged_widget->SetVisibilityChangedAnimationsEnabled(false);
   Attach(dragged_browser_view->tabstrip(), gfx::Point());
   AdjustBrowserAndTabBoundsForDrag(last_tabstrip_width,
@@ -1441,6 +1442,7 @@ void TabDragController::EndDragImpl(EndDragType type) {
         RestoreFocus();
       }
 
+      GetAttachedBrowserWidget()->SetCanAppearInExistingFullscreenSpaces(false);
       if (type == CANCELED)
         RevertDrag();
       else
@@ -1669,6 +1671,10 @@ void TabDragController::CompleteDrag() {
 
 void TabDragController::MaximizeAttachedWindow() {
   GetAttachedBrowserWidget()->Maximize();
+#if defined(OS_MACOSX)
+  if (was_source_fullscreen_)
+    GetAttachedBrowserWidget()->SetFullscreen(true);
+#endif
 #if defined(OS_CHROMEOS)
   if (was_source_fullscreen_) {
     // In fullscreen mode it is only possible to get here if the source

ui/gfx/mac/nswindow_frame_controls.mm

@@ -34,6 +34,8 @@ namespace gfx {
 
 void SetNSWindowCanFullscreen(NSWindow* window, bool allow_fullscreen) {
   NSWindowCollectionBehavior behavior = [window collectionBehavior];
+  if (behavior & NSWindowCollectionBehaviorFullScreenAuxiliary)
+    return;
   if (allow_fullscreen)
     behavior |= NSWindowCollectionBehaviorFullScreenPrimary;
   else

ui/views/widget/desktop_aura/desktop_native_widget_aura.cc

@@ -876,6 +876,9 @@ bool DesktopNativeWidgetAura::IsFullscreen() const {
   return content_window_ && desktop_window_tree_host_->IsFullscreen();
 }
 
+void DesktopNativeWidgetAura::SetCanAppearInExistingFullscreenSpaces(
+    bool can_appear_in_existing_fullscreen_spaces) {}
+
 void DesktopNativeWidgetAura::SetOpacity(float opacity) {
   if (content_window_)
     desktop_window_tree_host_->SetOpacity(opacity);

ui/views/widget/desktop_aura/desktop_native_widget_aura.h

@@ -162,6 +162,8 @@ class VIEWS_EXPORT DesktopNativeWidgetAura
   void Restore() override;
   void SetFullscreen(bool fullscreen) override;
   bool IsFullscreen() const override;
+  void SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces) override;
   void SetOpacity(float opacity) override;
   void SetAspectRatio(const gfx::SizeF& aspect_ratio) override;
   void FlashFrame(bool flash_frame) override;

ui/views/widget/native_widget_aura.cc

@@ -663,6 +663,9 @@ bool NativeWidgetAura::IsFullscreen() const {
       ui::SHOW_STATE_FULLSCREEN;
 }
 
+void NativeWidgetAura::SetCanAppearInExistingFullscreenSpaces(
+    bool can_appear_in_existing_fullscreen_spaces) {}
+
 void NativeWidgetAura::SetOpacity(float opacity) {
   if (window_)
     window_->layer()->SetOpacity(opacity);

ui/views/widget/native_widget_aura.h

@@ -123,6 +123,8 @@ class VIEWS_EXPORT NativeWidgetAura : public internal::NativeWidgetPrivate,
   void Restore() override;
   void SetFullscreen(bool fullscreen) override;
   bool IsFullscreen() const override;
+  void SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces) override;
   void SetOpacity(float opacity) override;
   void SetAspectRatio(const gfx::SizeF& aspect_ratio) override;
   void FlashFrame(bool flash_frame) override;

ui/views/widget/native_widget_mac.h

@@ -140,6 +140,8 @@ class VIEWS_EXPORT NativeWidgetMac : public internal::NativeWidgetPrivate {
   void Restore() override;
   void SetFullscreen(bool fullscreen) override;
   bool IsFullscreen() const override;
+  void SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces) override;
   void SetOpacity(float opacity) override;
   void SetAspectRatio(const gfx::SizeF& aspect_ratio) override;
   void FlashFrame(bool flash_frame) override;

ui/views/widget/native_widget_mac.mm

@@ -506,6 +506,14 @@ bool NativeWidgetMac::IsFullscreen() const {
   return bridge_host_ && bridge_host_->target_fullscreen_state();
 }
 
+void NativeWidgetMac::SetCanAppearInExistingFullscreenSpaces(
+    bool can_appear_in_existing_fullscreen_spaces) {
+  if (!bridge())
+    return;
+  bridge()->SetCanAppearInExistingFullscreenSpaces(
+      can_appear_in_existing_fullscreen_spaces);
+}
+
 void NativeWidgetMac::SetOpacity(float opacity) {
   if (!bridge())
     return;

ui/views/widget/native_widget_private.h

@@ -202,6 +202,8 @@ class VIEWS_EXPORT NativeWidgetPrivate : public NativeWidget {
   virtual void Restore() = 0;
   virtual void SetFullscreen(bool fullscreen) = 0;
   virtual bool IsFullscreen() const = 0;
+  virtual void SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces) = 0;
   virtual void SetOpacity(float opacity) = 0;
   virtual void SetAspectRatio(const gfx::SizeF& aspect_ratio) = 0;
   virtual void FlashFrame(bool flash) = 0;

ui/views/widget/widget.cc

@@ -728,6 +728,12 @@ bool Widget::IsFullscreen() const {
   return native_widget_->IsFullscreen();
 }
 
+void Widget::SetCanAppearInExistingFullscreenSpaces(
+    bool can_appear_in_existing_fullscreen_spaces) {
+  native_widget_->SetCanAppearInExistingFullscreenSpaces(
+      can_appear_in_existing_fullscreen_spaces);
+}
+
 void Widget::SetOpacity(float opacity) {
   DCHECK(opacity >= 0.0f);
   DCHECK(opacity <= 1.0f);

ui/views/widget/widget.h

@@ -555,6 +555,10 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
   void SetFullscreen(bool fullscreen);
   bool IsFullscreen() const;
 
+  // macOS: Sets whether the window can share fullscreen windows' spaces.
+  void SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces);
+
   // Sets the opacity of the widget. This may allow widgets behind the widget
   // in the Z-order to become visible, depending on the capabilities of the
   // underlying windowing system.

ui/views_bridge_mac/bridged_native_widget_impl.h

@@ -221,6 +221,8 @@ class VIEWS_EXPORT BridgedNativeWidgetImpl
       views_bridge_mac::mojom::VisibilityTransition transitions) override;
   void SetVisibleOnAllSpaces(bool always_visible) override;
   void SetFullscreen(bool fullscreen) override;
+  void SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces) override;
   void SetMiniaturized(bool miniaturized) override;
   void SetSizeConstraints(const gfx::Size& min_size,
                           const gfx::Size& max_size,

ui/views_bridge_mac/bridged_native_widget_impl.mm

@@ -1114,6 +1114,19 @@ void BridgedNativeWidgetImpl::SetFullscreen(bool fullscreen) {
   ToggleDesiredFullscreenState();
 }
 
+void BridgedNativeWidgetImpl::SetCanAppearInExistingFullscreenSpaces(
+    bool can_appear_in_existing_fullscreen_spaces) {
+  NSWindow* window = window_.get();
+  NSWindowCollectionBehavior collectionBehavior = window.collectionBehavior;
+  if (can_appear_in_existing_fullscreen_spaces) {
+    collectionBehavior |= NSWindowCollectionBehaviorFullScreenAuxiliary;
+    collectionBehavior &= ~NSWindowCollectionBehaviorFullScreenPrimary;
+  } else {
+    collectionBehavior &= ~NSWindowCollectionBehaviorFullScreenAuxiliary;
+  }
+  window.collectionBehavior = collectionBehavior;
+}
+
 void BridgedNativeWidgetImpl::SetMiniaturized(bool miniaturized) {
   if (miniaturized) {
     // Calling performMiniaturize: will momentarily highlight the button, but

ui/views_bridge_mac/mojo/bridged_native_widget.mojom

@@ -153,6 +153,11 @@ interface BridgedNativeWidget {
   // fullscreen state.
   SetFullscreen(bool fullscreen);
 
+  // Called by NativeWidgetMac; sets whether the window can share fullscreen
+  // windows' spaces by changing the NSWindow's collectionBehavior.
+  SetCanAppearInExistingFullscreenSpaces(
+      bool can_appear_in_existing_fullscreen_spaces);
+
   // Miniaturize or deminiaturize the window.
   SetMiniaturized(bool miniaturized);