[flutter_releases] Use PorterDuff blend mode when below Android 29 (#…

…34800) (#34930)

shell/platform/android/io/flutter/plugin/platform/PlatformViewWrapper.java

@@ -9,10 +9,10 @@
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
 import android.content.Context;
-import android.graphics.BlendMode;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Matrix;
+import android.graphics.PorterDuff;
 import android.graphics.Rect;
 import android.graphics.SurfaceTexture;
 import android.os.Build;
@@ -169,11 +169,7 @@ public void setTexture(@Nullable SurfaceTexture newTx) {
     // to the user until the platform view draws its first frame.
     final Canvas canvas = surface.lockHardwareCanvas();
     try {
-      if (Build.VERSION.SDK_INT >= 29) {
-        canvas.drawColor(Color.TRANSPARENT, BlendMode.CLEAR);
-      } else {
-        canvas.drawColor(Color.TRANSPARENT);
-      }
+      canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
       onFrameProduced();
     } finally {
       surface.unlockCanvasAndPost(canvas);
@@ -305,11 +301,7 @@ public void draw(Canvas canvas) {
       try {
         // Clear the current pixels in the canvas.
         // This helps when a WebView renders an HTML document with transparent background.
-        if (Build.VERSION.SDK_INT >= 29) {
-          surfaceCanvas.drawColor(Color.TRANSPARENT, BlendMode.CLEAR);
-        } else {
-          surfaceCanvas.drawColor(Color.TRANSPARENT);
-        }
+        surfaceCanvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
         super.draw(surfaceCanvas);
         onFrameProduced();
       } finally {

shell/platform/android/test/io/flutter/plugin/platform/PlatformViewWrapperTest.java

@@ -7,9 +7,9 @@
 
 import android.annotation.TargetApi;
 import android.content.Context;
-import android.graphics.BlendMode;
 import android.graphics.Canvas;
 import android.graphics.Color;
+import android.graphics.PorterDuff;
 import android.graphics.SurfaceTexture;
 import android.view.Surface;
 import android.view.View;
@@ -65,7 +65,7 @@ protected Surface createSurface(@NonNull SurfaceTexture tx) {
     // Verify.
     verify(surface, times(1)).lockHardwareCanvas();
     verify(surface, times(1)).unlockCanvasAndPost(canvas);
-    verify(canvas, times(1)).drawColor(Color.TRANSPARENT, BlendMode.CLEAR);
+    verify(canvas, times(1)).drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
     verifyNoMoreInteractions(surface);
     verifyNoMoreInteractions(canvas);
   }
@@ -112,7 +112,7 @@ public void draw(Canvas canvas) {
     wrapper.draw(new Canvas());
 
     // Verify.
-    verify(canvas, times(1)).drawColor(Color.TRANSPARENT, BlendMode.CLEAR);
+    verify(canvas, times(1)).drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
     verify(surface, times(1)).isValid();
     verify(surface, times(1)).lockHardwareCanvas();
     verify(surface, times(1)).unlockCanvasAndPost(canvas);