Use skia.mojom.BitmapN32 in QRCode mojoms

These bitmaps are safer for transport from untrustworthy sources since
all bitmaps should be in N32 format and the browser can make bad
assumptions as a result.

R=dcheng@chromium.org, sebsg@chromium.org

Bug: 1144462
Change-Id: I308ab745a5bfac1696be89e181b100d33db5d602
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2580026Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: sebsg <sebsg@chromium.org>
Commit-Queue: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#835198}

chrome/browser/share/qr_code_generation_request.cc

@@ -70,10 +70,6 @@ void QRCodeGenerationRequest::OnGenerateCodeResponse(
         env, java_qr_code_generation_request_, nullptr);
     return;
   }
-  // The QRCode service should be sending us N32 32bpp bitmaps in reply,
-  // otherwise this can lead to out-of-bounds mistakes when transferring the
-  // pixels out of the bitmap into other buffers.
-  CHECK_EQ(service_response->bitmap.colorType(), kN32_SkColorType);
 
   // Convert the result to a Java Bitmap.
   ScopedJavaLocalRef<jobject> java_bitmap =

chrome/services/qrcode_generator/public/mojom/qrcode_generator.mojom

@@ -56,7 +56,7 @@ struct GenerateQRCodeResponse {
 
   // Image data for generated QR code. May be null on error, or if rendering
   // was not requested.
-  skia.mojom.BitmapWithArbitraryBpp? bitmap;
+  skia.mojom.BitmapN32? bitmap;
 
   // QR Code data.
   array<uint8> data;