Fix nougat blank rendering with antialiased border radius clipping (facebook#56336)

Summary:
Pull Request resolved: facebook#56336

Moves `clipRect` inside the outer `saveLayer` in `clipWithAntiAliasing()` to fix blank rendering on API 24 (Nougat) devices.

facebook#55762 added `canvas.withClip()` to fix black pixels on partially off-screen views. However, it wrapped the entire compositing chain in an extra `save()`/`clipRect`/`restore()`, creating a triple-nested save/restore stack (`save` -> `saveLayer` -> `saveLayer(DST_IN)`) that breaks Porter-Duff compositing on API 24's HWUI renderer.

Moving `clipRect` inside the `saveLayer` reduces nesting from 3 to 2 levels while preserving the black-pixel mitigation. The `saveLayer` already saves and restores clip state, so a separate `save()`/`restore()` wrapper is unnecessary.

Changelog: [Android][Fixed] - Fix image content disappearing on API 24 (Nougat) when antialiased border radius clipping is applied

Reviewed By: NickGerleman

Differential Revision: D99677658

fbshipit-source-id: 55a9c84655cc08b05b95c29725492b9b8f759331

Author: Abbondanzo

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/BackgroundStyleApplicator.kt

@@ -20,7 +20,6 @@ import android.os.Build
 import android.view.View
 import android.widget.ImageView
 import androidx.annotation.ColorInt
-import androidx.core.graphics.withClip
 import com.facebook.react.bridge.ReadableArray
 import com.facebook.react.common.annotations.UnstableReactNativeAPI
 import com.facebook.react.uimanager.PixelUtil.dpToPx
@@ -573,49 +572,50 @@ public object BackgroundStyleApplicator {
       paddingBoxPath: Path,
       drawContent: () -> Unit,
   ) {
-    // Clip to the view's own bounds before saveLayer. On API <= 28 hardware-accelerated canvases,
+    // Save the layer for Porter-Duff compositing
+    val saveCount = canvas.saveLayer(0f, 0f, view.width.toFloat(), view.height.toFloat(), null)
+
+    // Clip to the view's own bounds inside the layer. On API <= 28 hardware-accelerated canvases,
     // the window boundary is tracked by the GPU scissor but not reflected in the canvas clip stack.
     // Without an explicit software clip, saveLayer may allocate a buffer with uninitialized pixels
-    // beyond the GPU scissor. Adding clipRect in the view's local coordinate space forces HWUI to
-    // include it in the clip stack, ensuring saveLayer properly constrains its buffer. This clip is
-    // stable across parent transform animations since it's in the view's own coordinate space.
-    canvas.withClip(0, 0, view.width, view.height) {
-      // Save the layer for Porter-Duff compositing
-      val saveCount = canvas.saveLayer(0f, 0f, view.width.toFloat(), view.height.toFloat(), null)
-
-      // Draw the content first
-      drawContent()
-
-      val maskPaint = Paint(Paint.ANTI_ALIAS_FLAG)
-      maskPaint.style = Paint.Style.FILL
-
-      // Transparent pixels with INVERSE_WINDING only works on API 28
-      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
-        maskPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.DST_IN)
-        maskPaint.color = Color.TRANSPARENT
-        paddingBoxPath.setFillType(Path.FillType.INVERSE_WINDING)
-        canvas.drawPath(paddingBoxPath, maskPaint)
-      } else {
-        // API < 28: Use a nested saveLayer with DST_IN compositing to mask content to the
-        // padding box path. EVEN_ODD fill + DST_OUT has rendering bugs on API 24's hardware
-        // renderer, so we avoid that technique. Instead, draw the mask shape into a separate
-        // layer; when restored with DST_IN, content is preserved only where the mask is opaque.
-        val dstInPaint = Paint()
-        dstInPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.DST_IN)
-        val maskSave =
-            canvas.saveLayer(0f, 0f, view.width.toFloat(), view.height.toFloat(), dstInPaint)
-        // Clear the layer to ensure it starts fully transparent. On API 24, saveLayer may not
-        // initialize the buffer to transparent, causing DST_IN to see non-zero alpha everywhere.
-        canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR)
-        maskPaint.xfermode = null
-        maskPaint.color = Color.BLACK
-        canvas.drawPath(paddingBoxPath, maskPaint)
-        canvas.restoreToCount(maskSave)
-      }
-
-      // Restore the layer
-      canvas.restoreToCount(saveCount)
+    // beyond the GPU scissor. Adding clipRect inside the layer (rather than wrapping it with
+    // canvas.withClip) avoids an extra save/restore nesting level that breaks Porter-Duff
+    // compositing on API 24's HWUI renderer. The saveLayer already saves and restores the clip
+    // state, so a separate save/restore wrapper is unnecessary.
+    canvas.clipRect(0, 0, view.width, view.height)
+
+    // Draw the content first
+    drawContent()
+
+    val maskPaint = Paint(Paint.ANTI_ALIAS_FLAG)
+    maskPaint.style = Paint.Style.FILL
+
+    // Transparent pixels with INVERSE_WINDING only works on API 28
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
+      maskPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.DST_IN)
+      maskPaint.color = Color.TRANSPARENT
+      paddingBoxPath.setFillType(Path.FillType.INVERSE_WINDING)
+      canvas.drawPath(paddingBoxPath, maskPaint)
+    } else {
+      // API < 28: Use a nested saveLayer with DST_IN compositing to mask content to the
+      // padding box path. EVEN_ODD fill + DST_OUT has rendering bugs on API 24's hardware
+      // renderer, so we avoid that technique. Instead, draw the mask shape into a separate
+      // layer; when restored with DST_IN, content is preserved only where the mask is opaque.
+      val dstInPaint = Paint()
+      dstInPaint.xfermode = PorterDuffXfermode(PorterDuff.Mode.DST_IN)
+      val maskSave =
+          canvas.saveLayer(0f, 0f, view.width.toFloat(), view.height.toFloat(), dstInPaint)
+      // Clear the layer to ensure it starts fully transparent. On API 24, saveLayer may not
+      // initialize the buffer to transparent, causing DST_IN to see non-zero alpha everywhere.
+      canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR)
+      maskPaint.xfermode = null
+      maskPaint.color = Color.BLACK
+      canvas.drawPath(paddingBoxPath, maskPaint)
+      canvas.restoreToCount(maskSave)
     }
+
+    // Restore the layer
+    canvas.restoreToCount(saveCount)
   }
 
   /**