Fix screen size with compatibility override scale

The values in dp shouldn't be changed because the density is
already scaled.

Also add unit tests to ensure that the override scale from
CompatModePackages applies to window and surface.

Bug: 168419799
Test: atest DisplayContentTeasts#testCompatOverrideScale
Change-Id: I4b99b123d4beb33cc3d97eb07e506d8a60fcc5e3

4 files changed, 47 insertions, 6 deletions

diff --git a/core/java/android/content/res/CompatibilityInfo.java b/core/java/android/content/res/CompatibilityInfo.java
index abf694f9742e..bbde8b103ef3 100644
--- a/core/java/android/content/res/CompatibilityInfo.java
+++ b/core/java/android/content/res/CompatibilityInfo.java
@@ -252,9 +252,10 @@ public class CompatibilityInfo implements Parcelable {
             }
 
             if (overrideScale != 1.0f) {
-                applicationDensity = DisplayMetrics.DENSITY_DEFAULT;
                 applicationScale = overrideScale;
                 applicationInvertedScale = 1.0f / overrideScale;
+                applicationDensity = (int) ((DisplayMetrics.DENSITY_DEVICE_STABLE
+                        * applicationInvertedScale) + .5f);
                 compatFlags |= HAS_OVERRIDE_SCALING;
             } else if ((appInfo.flags & ApplicationInfo.FLAG_SUPPORTS_SCREEN_DENSITIES) != 0) {
                 applicationDensity = DisplayMetrics.DENSITY_DEVICE;
@@ -519,10 +520,6 @@ public class CompatibilityInfo implements Parcelable {
         if (isScalingRequired()) {
             float invertedRatio = applicationInvertedScale;
             inoutConfig.densityDpi = (int)((inoutConfig.densityDpi * invertedRatio) + .5f);
-            inoutConfig.screenWidthDp = (int) ((inoutConfig.screenWidthDp * invertedRatio) + .5f);
-            inoutConfig.screenHeightDp = (int) ((inoutConfig.screenHeightDp * invertedRatio) + .5f);
-            inoutConfig.smallestScreenWidthDp =
-                    (int) ((inoutConfig.smallestScreenWidthDp * invertedRatio) + .5f);
             inoutConfig.windowConfiguration.getMaxBounds().scale(invertedRatio);
             inoutConfig.windowConfiguration.getBounds().scale(invertedRatio);
             final Rect appBounds = inoutConfig.windowConfiguration.getAppBounds();
diff --git a/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java b/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java
index b4fd3024a634..781cfec77f08 100644
--- a/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/DisplayContentTests.java
@@ -1834,7 +1834,7 @@ public class DisplayContentTests extends WindowTestsBase {
         mWm.updateFocusedWindowLocked(UPDATE_FOCUS_NORMAL, false /* updateInputWindows */);
     }
 
-    private void performLayout(DisplayContent dc) {
+    static void performLayout(DisplayContent dc) {
         dc.setLayoutNeeded();
         dc.performLayout(true /* initial */, false /* updateImeWindows */);
     }
diff --git a/services/tests/wmtests/src/com/android/server/wm/WindowStateTests.java b/services/tests/wmtests/src/com/android/server/wm/WindowStateTests.java
index 3231f8b6551a..896969548af3 100644
--- a/services/tests/wmtests/src/com/android/server/wm/WindowStateTests.java
+++ b/services/tests/wmtests/src/com/android/server/wm/WindowStateTests.java
@@ -67,11 +67,14 @@ import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.clearInvocations;
 import static org.mockito.Mockito.when;
 
+import android.content.res.CompatibilityInfo;
+import android.content.res.Configuration;
 import android.graphics.Matrix;
 import android.graphics.Rect;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.platform.test.annotations.Presubmit;
+import android.view.Gravity;
 import android.view.InputWindowHandle;
 import android.view.InsetsState;
 import android.view.SurfaceControl;
@@ -559,6 +562,46 @@ public class WindowStateTests extends WindowTestsBase {
         assertTrue(window.isVisibleByPolicy());
     }
 
+    @Test
+    public void testCompatOverrideScale() {
+        final float overrideScale = 2; // 0.5x on client side.
+        final CompatModePackages cmp = mWm.mAtmService.mCompatModePackages;
+        spyOn(cmp);
+        doReturn(overrideScale).when(cmp).getCompatScale(anyString(), anyInt());
+        final WindowState w = createWindow(null, TYPE_APPLICATION_OVERLAY, "win");
+        makeWindowVisible(w);
+        w.setRequestedSize(100, 200);
+        w.mAttrs.width = w.mAttrs.height = WindowManager.LayoutParams.WRAP_CONTENT;
+        w.mAttrs.gravity = Gravity.TOP | Gravity.LEFT;
+        DisplayContentTests.performLayout(mDisplayContent);
+
+        // Frame on screen = 100x200. Compat frame on client = 50x100.
+        final Rect unscaledCompatFrame = new Rect(w.getWindowFrames().mCompatFrame);
+        unscaledCompatFrame.scale(overrideScale);
+        assertEquals(w.getWindowFrames().mFrame, unscaledCompatFrame);
+
+        // Surface should apply the scale.
+        w.prepareSurfaces();
+        verify(w.getPendingTransaction()).setMatrix(w.getSurfaceControl(),
+                overrideScale, 0, 0, overrideScale);
+
+        // According to "dp * density / 160 = px", density is scaled and the size in dp is the same.
+        final CompatibilityInfo compatInfo = cmp.compatibilityInfoForPackageLocked(
+                mContext.getApplicationInfo());
+        final Configuration winConfig = w.getConfiguration();
+        final Configuration clientConfig = new Configuration(w.getConfiguration());
+        compatInfo.applyToConfiguration(clientConfig.densityDpi, clientConfig);
+
+        assertEquals(winConfig.screenWidthDp, clientConfig.screenWidthDp);
+        assertEquals(winConfig.screenHeightDp, clientConfig.screenHeightDp);
+        assertEquals(winConfig.smallestScreenWidthDp, clientConfig.smallestScreenWidthDp);
+        assertEquals(winConfig.densityDpi, (int) (clientConfig.densityDpi * overrideScale));
+
+        final Rect unscaledClientBounds = new Rect(clientConfig.windowConfiguration.getBounds());
+        unscaledClientBounds.scale(overrideScale);
+        assertEquals(w.getWindowConfiguration().getBounds(), unscaledClientBounds);
+    }
+
     @UseTestDisplay(addWindows = { W_ABOVE_ACTIVITY, W_NOTIFICATION_SHADE })
     @Test
     public void testRequestDrawIfNeeded() {
diff --git a/services/tests/wmtests/src/com/android/server/wm/WindowTestsBase.java b/services/tests/wmtests/src/com/android/server/wm/WindowTestsBase.java
index eb6c6ed349de..83b30a9747d7 100644
--- a/services/tests/wmtests/src/com/android/server/wm/WindowTestsBase.java
+++ b/services/tests/wmtests/src/com/android/server/wm/WindowTestsBase.java
@@ -337,6 +337,7 @@ class WindowTestsBase extends SystemServiceTestsBase {
 
         final WindowManager.LayoutParams attrs = new WindowManager.LayoutParams(type);
         attrs.setTitle(name);
+        attrs.packageName = "test";
 
         final WindowState w = new WindowState(service, session, iWindow, token, parent,
                 OP_NONE, attrs, VISIBLE, ownerId, userId,