[Chromecast] Add CastContentWindow::NotifyVisibilityChange

By default, this should just propagate visibility information to the
delegate. In the future, NotifyVisibilityChange should only be called
by the window manager. Documentation for CastContentWindow was improved
as a minor clean up.

Bug: internal b/79874784
Test: CQ
Change-Id: I3eab9b60b74037cd1f122e03460d0b8fe6db00c0
Reviewed-on: https://chromium-review.googlesource.com/1086042
Commit-Queue: Sean Topping <seantopping@chromium.org>
Reviewed-by: Stephen Lanham <slan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#564644}

chromecast/browser/android/cast_content_window_android.cc

@@ -103,6 +103,11 @@ void CastContentWindowAndroid::RequestVisibility(
       env, java_window_, static_cast<int>(visibility_priority));
 }
 
+void CastContentWindowAndroid::NotifyVisibilityChange(
+    VisibilityType visibility_type) {
+  delegate_->OnVisibilityChange(visibility_type);
+}
+
 void CastContentWindowAndroid::RequestMoveOut() {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_CastContentWindowAndroid_requestMoveOut(env, java_window_);
@@ -119,7 +124,7 @@ void CastContentWindowAndroid::OnVisibilityChange(
     JNIEnv* env,
     const base::android::JavaParamRef<jobject>& jcaller,
     int visibility_type) {
-  delegate_->OnVisibilityChange(static_cast<VisibilityType>(visibility_type));
+  NotifyVisibilityChange(static_cast<VisibilityType>(visibility_type));
 }
 
 base::android::ScopedJavaLocalRef<jstring> CastContentWindowAndroid::GetId(

chromecast/browser/android/cast_content_window_android.h

@@ -31,11 +31,9 @@ class CastContentWindowAndroid : public CastContentWindow {
       bool is_visible,
       CastWindowManager::WindowId z_order,
       VisibilityPriority visibility_priority) override;
-
   void EnableTouchInput(bool enabled) override;
-
   void RequestVisibility(VisibilityPriority visibility_priority) override;
-
+  void NotifyVisibilityChange(VisibilityType visibility_type) override;
   void RequestMoveOut() override;
 
   // Called through JNI.

chromecast/browser/cast_content_window.h

@@ -17,13 +17,29 @@
 namespace chromecast {
 namespace shell {
 
+// Describes visual context of the window within the UI.
 enum class VisibilityType {
+  // Unknown visibility state.
   UNKNOWN = 0,
+
+  // Window is occupying the entire screen and can be interacted with.
   FULL_SCREEN = 1,
+
+  // Window occupies a portion of the screen, supporting user interaction.
   PARTIAL_OUT = 2,
-  HIDDEN = 3
+
+  // Window is hidden, and cannot be interacted with via touch.
+  HIDDEN = 3,
+
+  // Window is being displayed as a small visible tile.
+  TILE = 4
 };
 
+// Represents requested activity windowing behavior. Behavior includes:
+// 1. How long the activity should show
+// 2. Whether the window should become immediately visible
+// 3. How much screen space the window should occupy
+// 4. What state to return to when the activity is completed
 enum class VisibilityPriority {
   // Default priority. It is up to system to decide how to show the activity.
   DEFAULT = 0,
@@ -110,6 +126,11 @@ class CastContentWindow {
   // change.
   virtual void RequestVisibility(VisibilityPriority visibility_priority) = 0;
 
+  // Notify the window that its visibility type has changed. This should only
+  // ever be called by the window manager.
+  // TODO(seantopping): Make this private to the window manager.
+  virtual void NotifyVisibilityChange(VisibilityType visibility_type) = 0;
+
   // Cast activity or application calls it to request for moving out of the
   // screen.
   virtual void RequestMoveOut() = 0;

chromecast/browser/cast_content_window_aura.cc

@@ -77,9 +77,12 @@ std::unique_ptr<CastContentWindow> CastContentWindow::Create(
 CastContentWindowAura::CastContentWindowAura(
     CastContentWindow::Delegate* delegate,
     bool is_touch_enabled)
-    : back_gesture_dispatcher_(
-          std::make_unique<CastBackGestureDispatcher>(delegate)),
-      is_touch_enabled_(is_touch_enabled) {}
+    : delegate_(delegate),
+      back_gesture_dispatcher_(
+          std::make_unique<CastBackGestureDispatcher>(delegate_)),
+      is_touch_enabled_(is_touch_enabled) {
+  DCHECK(delegate_);
+}
 
 CastContentWindowAura::~CastContentWindowAura() {
   if (window_manager_)
@@ -118,6 +121,11 @@ void CastContentWindowAura::EnableTouchInput(bool enabled) {
 void CastContentWindowAura::RequestVisibility(
     VisibilityPriority visibility_priority){};
 
+void CastContentWindowAura::NotifyVisibilityChange(
+    VisibilityType visibility_type) {
+  delegate_->OnVisibilityChange(visibility_type);
+}
+
 void CastContentWindowAura::RequestMoveOut(){};
 
 bool CastContentWindowAura::CanHandleSwipe(CastSideSwipeOrigin swipe_origin) {

chromecast/browser/cast_content_window_aura.h

@@ -32,6 +32,7 @@ class CastContentWindowAura : public CastContentWindow,
       CastWindowManager::WindowId z_order,
       VisibilityPriority visibility_priority) override;
   void RequestVisibility(VisibilityPriority visibility_priority) override;
+  void NotifyVisibilityChange(VisibilityType visibility_type) override;
   void RequestMoveOut() override;
   void EnableTouchInput(bool enabled) override;
 
@@ -48,6 +49,8 @@ class CastContentWindowAura : public CastContentWindow,
   // This class should only be instantiated by CastContentWindow::Create.
   CastContentWindowAura(Delegate* delegate, bool is_touch_enabled);
 
+  CastContentWindow::Delegate* const delegate_;
+
   // Utility class for detecting and dispatching back gestures to delegates.
   std::unique_ptr<CastBackGestureDispatcher> back_gesture_dispatcher_;