[Fullscreen Control] Don't show exit UI if slide-down top-chrome is available

If the slide-down top-chrome is available in fullscreen mode then we
don't need to show the fullscreen exit UI since the user can use the
top-chrome to exit fullscreen.

Bug: 758456
Change-Id: I1298279ca97e5fea00629e888e6a56ade23bc67f
Reviewed-on: https://chromium-review.googlesource.com/827608Reviewed-by: Robert Liao <robliao@chromium.org>
Commit-Queue: Yuwei Huang <yuweih@chromium.org>
Cr-Commit-Position: refs/heads/master@{#524209}

chrome/browser/ui/views/fullscreen_control/fullscreen_control_host.cc

@@ -62,7 +62,7 @@ void FullscreenControlHost::OnMouseEvent(ui::MouseEvent* event) {
     return;
   }
 
-  if (browser_view_->IsFullscreen()) {
+  if (IsExitUiNeeded()) {
     if (IsVisible()) {
       float control_bottom = static_cast<float>(
           fullscreen_control_popup_.GetFinalBounds().bottom());
@@ -98,8 +98,8 @@ void FullscreenControlHost::OnTouchEvent(ui::TouchEvent* event) {
 }
 
 void FullscreenControlHost::OnGestureEvent(ui::GestureEvent* event) {
-  if (event->type() == ui::ET_GESTURE_LONG_PRESS &&
-      browser_view_->IsFullscreen() && !IsVisible()) {
+  if (event->type() == ui::ET_GESTURE_LONG_PRESS && IsExitUiNeeded() &&
+      !IsVisible()) {
     ShowForInputEntryMethod(InputEntryMethod::TOUCH);
   }
 }
@@ -132,3 +132,8 @@ void FullscreenControlHost::OnTouchPopupTimeout() {
     Hide(true);
   }
 }
+
+bool FullscreenControlHost::IsExitUiNeeded() {
+  return browser_view_->IsFullscreen() &&
+         browser_view_->ShouldHideUIForFullscreen();
+}

chrome/browser/ui/views/fullscreen_control/fullscreen_control_host.h

@@ -55,6 +55,7 @@ class FullscreenControlHost : public ui::EventHandler {
   void ShowForInputEntryMethod(InputEntryMethod input_entry_method);
   void OnVisibilityChanged();
   void OnTouchPopupTimeout();
+  bool IsExitUiNeeded();
 
   InputEntryMethod input_entry_method_ = InputEntryMethod::NOT_ACTIVE;