Add isRound to WindowInsets

isRound allows a view to determine whether the window it is contained
within obscures the corners of the window content. This allows views
aware of this property to adapt their layout accordingly.

Switch ViewRootImpl to use dispatchApplyInsets instead of
fitSystemWindows.

Change-Id: Ic3e3936b73815b2593cb9720af1a309fbd18406e
diff --git a/api/current.txt b/api/current.txt
index b163bd3..9bf7674 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -30958,6 +30958,7 @@
     method public boolean hasInsets();
     method public boolean hasSystemWindowInsets();
     method public boolean hasWindowDecorInsets();
+    method public boolean isRound();
   }
 
   public abstract interface WindowManager implements android.view.ViewManager {
diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java
index ef22def..eec4354 100644
--- a/core/java/android/view/ViewRootImpl.java
+++ b/core/java/android/view/ViewRootImpl.java
@@ -1171,6 +1171,11 @@
         m.preTranslate(-attachInfo.mWindowLeft, -attachInfo.mWindowTop);
     }
 
+    void dispatchApplyInsets(View host) {
+        mFitSystemWindowsInsets.set(mAttachInfo.mContentInsets);
+        host.dispatchApplyWindowInsets(new WindowInsets(mFitSystemWindowsInsets));
+    }
+
     private void performTraversals() {
         // cache mView since it is used so much below...
         final View host = mView;
@@ -1257,8 +1262,7 @@
             }
             host.dispatchAttachedToWindow(attachInfo, 0);
             attachInfo.mTreeObserver.dispatchOnWindowAttachedChange(true);
-            mFitSystemWindowsInsets.set(mAttachInfo.mContentInsets);
-            host.fitSystemWindows(mFitSystemWindowsInsets);
+            dispatchApplyInsets(host);
             //Log.i(TAG, "Screen on initialized: " + attachInfo.mKeepScreenOn);
 
         } else {
@@ -1383,9 +1387,8 @@
 
         if (mFitSystemWindowsRequested) {
             mFitSystemWindowsRequested = false;
-            mFitSystemWindowsInsets.set(mAttachInfo.mContentInsets);
             mLastOverscanRequested = mAttachInfo.mOverscanRequested;
-            host.fitSystemWindows(mFitSystemWindowsInsets);
+            dispatchApplyInsets(host);
             if (mLayoutRequested) {
                 // Short-circuit catching a new layout request here, so
                 // we don't need to go through two layout passes when things
@@ -1559,8 +1562,7 @@
                     mLastSystemUiVisibility = mAttachInfo.mSystemUiVisibility;
                     mLastOverscanRequested = mAttachInfo.mOverscanRequested;
                     mFitSystemWindowsRequested = false;
-                    mFitSystemWindowsInsets.set(mAttachInfo.mContentInsets);
-                    host.fitSystemWindows(mFitSystemWindowsInsets);
+                    dispatchApplyInsets(host);
                 }
                 if (visibleInsetsChanged) {
                     mAttachInfo.mVisibleInsets.set(mPendingVisibleInsets);
diff --git a/core/java/android/view/WindowInsets.java b/core/java/android/view/WindowInsets.java
index cdfcb43..f8cc793 100644
--- a/core/java/android/view/WindowInsets.java
+++ b/core/java/android/view/WindowInsets.java
@@ -33,6 +33,7 @@
     private Rect mSystemWindowInsets;
     private Rect mWindowDecorInsets;
     private Rect mTempRect;
+    private boolean mIsRound;
 
     private static final Rect EMPTY_RECT = new Rect(0, 0, 0, 0);
 
@@ -46,8 +47,14 @@
 
     /** @hide */
     public WindowInsets(Rect systemWindowInsets, Rect windowDecorInsets) {
+        this(systemWindowInsets, windowDecorInsets, false);
+    }
+
+    /** @hide */
+    public WindowInsets(Rect systemWindowInsets, Rect windowDecorInsets, boolean isRound) {
         mSystemWindowInsets = systemWindowInsets;
         mWindowDecorInsets = windowDecorInsets;
+        mIsRound = isRound;
     }
 
     /**
@@ -58,12 +65,12 @@
     public WindowInsets(WindowInsets src) {
         mSystemWindowInsets = src.mSystemWindowInsets;
         mWindowDecorInsets = src.mWindowDecorInsets;
+        mIsRound = src.mIsRound;
     }
 
     /** @hide */
     public WindowInsets(Rect systemWindowInsets) {
-        mSystemWindowInsets = systemWindowInsets;
-        mWindowDecorInsets = EMPTY_RECT;
+        this(systemWindowInsets, EMPTY_RECT);
     }
 
     /**
@@ -220,6 +227,20 @@
         return hasSystemWindowInsets() || hasWindowDecorInsets();
     }
 
+    /**
+     * Returns true if the associated window has a round shape.
+     *
+     * <p>A round window's left, top, right and bottom edges reach all the way to the
+     * associated edges of the window but the corners may not be visible. Views responding
+     * to round insets should take care to not lay out critical elements within the corners
+     * where they may not be accessible.</p>
+     *
+     * @return True if the window is round
+     */
+    public boolean isRound() {
+        return mIsRound;
+    }
+
     public WindowInsets cloneWithSystemWindowInsetsConsumed() {
         final WindowInsets result = new WindowInsets(this);
         result.mSystemWindowInsets = new Rect(0, 0, 0, 0);
@@ -273,6 +294,6 @@
     @Override
     public String toString() {
         return "WindowInsets{systemWindowInsets=" + mSystemWindowInsets + " windowDecorInsets=" +
-                mWindowDecorInsets + "}";
+                mWindowDecorInsets + (isRound() ? "round}" : "}");
     }
 }