browser: Fix caption buttons after drag from an overview grid to another

The present CL follows up after [1] which implements functionality where
you can drag an overview window from one display and drop into overview
on another display. The problem is that after you do so with a browser
window and then end overview, the caption buttons (Minimize, Maximize,
and Close) on that browser window may not work. I observe the problem on
a test device (nautilus) but not in the emulator.

[1] https://chromium-review.googlesource.com/c/chromium/src/+/2008237

Bug: 961170
Change-Id: I15f6bcec8116cbe853737682735865a77827d196
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2013866
Commit-Queue: Avery Musbach <amusbach@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#734699}

chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.cc

@@ -600,19 +600,13 @@ void BrowserNonClientFrameViewAsh::OnProfileAvatarChanged(
 // BrowserNonClientFrameViewAsh, private:
 
 bool BrowserNonClientFrameViewAsh::ShouldShowCaptionButtons() const {
-  // In tablet mode, to prevent accidental taps of the window controls, and to
-  // give more horizontal space for tabs and the new tab button especially in
-  // splitscreen view, we hide the window controls. We only do this when the
-  // Home Launcher feature is enabled, since it gives the user the ability to
-  // minimize all windows when pressing the Launcher button on the shelf.
-  const bool hide_caption_buttons_in_tablet_mode =
-      !UsePackagedAppHeaderStyle(browser_view()->browser());
-  if (hide_caption_buttons_in_tablet_mode &&
-      ash::TabletMode::Get()->InTabletMode()) {
-    return false;
-  }
+  return ShouldShowCaptionButtonsWhenNotInOverview() && !IsInOverviewMode();
+}
 
-  return !IsInOverviewMode();
+bool BrowserNonClientFrameViewAsh::ShouldShowCaptionButtonsWhenNotInOverview()
+    const {
+  return UsePackagedAppHeaderStyle(browser_view()->browser()) ||
+         !ash::TabletMode::Get()->InTabletMode();
 }
 
 int BrowserNonClientFrameViewAsh::GetToolbarLeftInset() const {
@@ -632,7 +626,7 @@ int BrowserNonClientFrameViewAsh::GetTabStripLeftInset() const {
 
 int BrowserNonClientFrameViewAsh::GetTabStripRightInset() const {
   int inset = 0;
-  if (ShouldShowCaptionButtons())
+  if (ShouldShowCaptionButtonsWhenNotInOverview())
     inset += caption_button_container_->GetPreferredSize().width();
   if (web_app_frame_toolbar())
     inset += web_app_frame_toolbar()->GetPreferredSize().width();

chrome/browser/ui/views/frame/browser_non_client_frame_view_ash.h

@@ -152,10 +152,19 @@ class BrowserNonClientFrameViewAsh
 
   friend class WebAppNonClientFrameViewAshTest;
 
-  // Returns whether the caption buttons should be visible. They are hidden, for
-  // example, in overview mode and tablet mode.
+  // Returns true if |ShouldShowCaptionButtonsWhenNotInOverview| returns true
+  // and this browser window is not showing in overview.
   bool ShouldShowCaptionButtons() const;
 
+  // In tablet mode, to prevent accidental taps of the window controls, and to
+  // give more horizontal space for tabs and the new tab button (especially in
+  // split view), we hide the window controls even when this browser window is
+  // not showing in overview. We only do this when the Home Launcher feature is
+  // enabled, because it gives the user the ability to minimize all windows when
+  // pressing the Launcher button on the shelf. So, this function returns true
+  // if the Home Launcher feature is disabled or we are in clamshell mode.
+  bool ShouldShowCaptionButtonsWhenNotInOverview() const;
+
   // Distance between the edge of the NonClientFrameView and the web app frame
   // toolbar.
   int GetToolbarLeftInset() const;