Stop using GrBackendSurface's pixel config

Note: I'll follow this up with a separate CL that removes the pixel config

Bug: skia:6718
Change-Id: If069afa95bd51d5d6b24089fd3a8526e4d982820
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/228257
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/src/image/SkImage_GpuBase.cpp b/src/image/SkImage_GpuBase.cpp
index e2f70ae..201daad 100644
--- a/src/image/SkImage_GpuBase.cpp
+++ b/src/image/SkImage_GpuBase.cpp
@@ -56,6 +56,10 @@
         return false;
     }
 
+    if (!ctx->priv().caps()->areColorTypeAndFormatCompatible(grCT, backendFormat)) {
+        return false;
+    }
+
     *config = ctx->priv().caps()->getConfigFromBackendFormat(backendFormat, grCT);
     return *config != kUnknown_GrPixelConfig;
 }
@@ -249,6 +253,7 @@
         if (!backendFormat.isValid()) {
             return false;
         }
+
         yuvaTexturesCopy[textureIndex].fConfig =
                 caps->getYUVAConfigFromBackendFormat(backendFormat);
         if (yuvaTexturesCopy[textureIndex].fConfig == kUnknown_GrPixelConfig) {