Let insets sources can produce insets on 0-width or 0-height windows

Window Manager allows the client to add 0-width or 0-height windows.
These windows can get insets in the legacy insets mode even they only
intersect with the insets source window on the edges. This CL make this
behavior compatible with the legacy insets mode.

Fix: 150696052
Test: atest InsetsSourceTest
Change-Id: I9ed76bb615a0133ad55e1f93b22fbc03ae5cb437

1 files changed, 24 insertions, 2 deletions

diff --git a/core/java/android/view/InsetsSource.java b/core/java/android/view/InsetsSource.java
index 719f649cb5a2..294faaf0b5c8 100644
--- a/core/java/android/view/InsetsSource.java
+++ b/core/java/android/view/InsetsSource.java
@@ -18,6 +18,7 @@ package android.view;
 
 import static android.view.InsetsState.ITYPE_IME;
 
+import android.annotation.NonNull;
 import android.annotation.Nullable;
 import android.graphics.Insets;
 import android.graphics.Rect;
@@ -114,7 +115,7 @@ public class InsetsSource implements Parcelable {
         if (!ignoreVisibility && !mVisible) {
             return Insets.NONE;
         }
-        if (!mTmpFrame.setIntersect(frame, relativeFrame)) {
+        if (!getIntersection(frame, relativeFrame, mTmpFrame)) {
             return Insets.NONE;
         }
 
@@ -144,12 +145,33 @@ public class InsetsSource implements Parcelable {
         }
     }
 
+    /**
+     * Outputs the intersection of two rectangles. The shared edges will also be counted in the
+     * intersection.
+     *
+     * @param a The first rectangle being intersected with.
+     * @param b The second rectangle being intersected with.
+     * @param out The rectangle which represents the intersection.
+     * @return {@code true} if there is any intersection.
+     */
+    private static boolean getIntersection(@NonNull Rect a, @NonNull Rect b, @NonNull Rect out) {
+        if (a.left <= b.right && b.left <= a.right && a.top <= b.bottom && b.top <= a.bottom) {
+            out.left = Math.max(a.left, b.left);
+            out.top = Math.max(a.top, b.top);
+            out.right = Math.min(a.right, b.right);
+            out.bottom = Math.min(a.bottom, b.bottom);
+            return true;
+        }
+        out.setEmpty();
+        return false;
+    }
+
     public void dump(String prefix, PrintWriter pw) {
         pw.print(prefix);
         pw.print("InsetsSource type="); pw.print(InsetsState.typeToString(mType));
         pw.print(" frame="); pw.print(mFrame.toShortString());
         if (mVisibleFrame != null) {
-            pw.print(" visibleFrmae="); pw.print(mVisibleFrame.toShortString());
+            pw.print(" visibleFrame="); pw.print(mVisibleFrame.toShortString());
         }
         pw.print(" visible="); pw.print(mVisible);
         pw.println();