ActivationTrackerWin: General refactor, renaming and clarification.

chrome/browser/ui/views/app_list/win/activation_tracker_win.cc

Index: chrome/browser/ui/views/app_list/win/activation_tracker_win.cc
diff --git a/chrome/browser/ui/views/app_list/win/activation_tracker_win.cc b/chrome/browser/ui/views/app_list/win/activation_tracker_win.cc
index b1d5a52c85fe8c41da296360c09110d4f2568242..4574703202e9fd65c0d0973a2a2587a5963e26b9 100644
--- a/chrome/browser/ui/views/app_list/win/activation_tracker_win.cc
+++ b/chrome/browser/ui/views/app_list/win/activation_tracker_win.cc
@@ -8,7 +8,9 @@
 
 namespace {
 
+static const wchar_t kJumpListClassName[] = L"DV2ControlHost";
 static const wchar_t kTrayClassName[] = L"Shell_TrayWnd";
+static const int kFocusCheckIntervalMS = 250;
 
 }  // namespace
 
@@ -17,8 +19,8 @@ ActivationTrackerWin::ActivationTrackerWin(
     const base::Closure& on_should_dismiss)
     : view_(view),
       on_should_dismiss_(on_should_dismiss),
-      regain_next_lost_focus_(false),
-      preserving_focus_for_taskbar_menu_(false) {
+      reactivate_on_next_focus_loss_(false),
+      taskbar_has_focus_(false) {
   view_->AddObserver(this);
 }
 
@@ -28,37 +30,55 @@ ActivationTrackerWin::~ActivationTrackerWin() {
 }
 
 void ActivationTrackerWin::OnActivationChanged(
-    views::Widget* widget, bool active) {
-  const int kFocusCheckIntervalMS = 250;
+    views::Widget* /*widget*/, bool active) {
   if (active) {
     timer_.Stop();
     return;
   }
 
-  preserving_focus_for_taskbar_menu_ = false;
+  taskbar_has_focus_ = false;
   timer_.Start(FROM_HERE,
                base::TimeDelta::FromMilliseconds(kFocusCheckIntervalMS), this,
-               &ActivationTrackerWin::CheckTaskbarOrViewHasFocus);
+               &ActivationTrackerWin::MaybeDismissAppList);
 }
 
 void ActivationTrackerWin::OnViewHidden() {
   timer_.Stop();
 }
 
-void ActivationTrackerWin::CheckTaskbarOrViewHasFocus() {
+void ActivationTrackerWin::MaybeDismissAppList() {
+  if (!ShouldDismissAppList())
+    return;
+
+  if (reactivate_on_next_focus_loss_) {
+    // Instead of dismissing the app launcher, re-activate it.
+    reactivate_on_next_focus_loss_ = false;
+    view_->GetWidget()->Activate();
+    return;
+  }
+
+  on_should_dismiss_.Run();
+}
+
+bool ActivationTrackerWin::ShouldDismissAppList() {
+  // The app launcher should be hidden when it loses focus, except for the cases
+  // necessary to allow the launcher to be pinned or closed via the taskbar
+  // context menu. This will return true to dismiss the app launcher unless one
+  // of the following conditions are met:
+  // - the app launcher is focused, or
+  // - the taskbar's jump list is focused, or
+  // - the taskbar is focused with the right mouse button pressed.
+
   // Remember if the taskbar had focus without the right mouse button being
   // down.
-  bool was_preserving_focus = preserving_focus_for_taskbar_menu_;
-  preserving_focus_for_taskbar_menu_ = false;
+  bool taskbar_had_focus = taskbar_has_focus_;
+  taskbar_has_focus_ = false;
 
   // First get the taskbar and jump lists windows (the jump list is the
   // context menu which the taskbar uses).
-  HWND jump_list_hwnd = FindWindow(L"DV2ControlHost", NULL);
+  HWND jump_list_hwnd = FindWindow(kJumpListClassName, NULL);
   HWND taskbar_hwnd = FindWindow(kTrayClassName, NULL);
 
-  // This code is designed to hide the app launcher when it loses focus,
-  // except for the cases necessary to allow the launcher to be pinned or
-  // closed via the taskbar context menu.
   // First work out if the left or right button is currently down.
   int swapped = GetSystemMetrics(SM_SWAPBUTTON);
   int left_button = swapped ? VK_RBUTTON : VK_LBUTTON;
@@ -70,52 +90,38 @@ void ActivationTrackerWin::CheckTaskbarOrViewHasFocus() {
   HWND focused_hwnd = GetForegroundWindow();
   if (!focused_hwnd) {
     // Sometimes the focused window is NULL. This can happen when the focus is
-    // changing due to a mouse button press. If the button is still being
-    // pressed the launcher should not be hidden.
-    if (right_button_down || left_button_down)
-      return;
-
-    // If the focused window is NULL, and the mouse button is not being
-    // pressed, then the launcher no longer has focus.
-    on_should_dismiss_.Run();
-    return;
+    // changing due to a mouse button press. Dismiss the launcher if and only if
+    // no button is being pressed.
+    return !right_button_down && !left_button_down;
   }
 
   while (focused_hwnd) {
     // If the focused window is the right click menu (called a jump list) or
     // the app list, don't hide the launcher.
-    if (focused_hwnd == jump_list_hwnd ||
-        focused_hwnd == view_->GetHWND()) {
-      return;
-    }
+    if (focused_hwnd == jump_list_hwnd || focused_hwnd == view_->GetHWND())
+      return false;
 
     if (focused_hwnd == taskbar_hwnd) {
       // If the focused window is the taskbar, and the right button is down,
       // don't hide the launcher as the user might be bringing up the menu.
       if (right_button_down)
-        return;
+        return false;
 
       // There is a short period between the right mouse button being down
       // and the menu gaining focus, where the taskbar has focus and no button
-      // is down. If the taskbar is observed in this state once the launcher
-      // is not dismissed. If it happens twice in a row it is dismissed.
-      if (!was_preserving_focus) {
-        preserving_focus_for_taskbar_menu_ = true;
-        return;
+      // is down. If the taskbar is observed in this state one time, the
+      // launcher is not dismissed. If it happens for two consecutive timer
+      // ticks, it is dismissed.
+      if (!taskbar_had_focus) {
+        taskbar_has_focus_ = true;
+        return false;
       }
-
-      break;
+      return true;
     }
     focused_hwnd = GetParent(focused_hwnd);
   }
 
-  if (regain_next_lost_focus_) {
-    regain_next_lost_focus_ = false;
-    view_->GetWidget()->Activate();
-    return;
-  }
-
-  // If we get here, the focused window is not the taskbar, it's context menu,
-  // or the app list.
-  on_should_dismiss_.Run();
+  // If we get here, the focused window is not the taskbar, its context menu, or
+  // the app list.
+  return true;
 }