Add new SkImage factory to create from GrBackendTexture with SkColorType

Bug: skia:
Change-Id: I46bdc54b6d9cdacc8f5a06644aa6b110837879f0
Reviewed-on: https://skia-review.googlesource.com/84342
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/tools/gpu/GrTest.cpp b/tools/gpu/GrTest.cpp
index 552dd8a..f511574 100644
--- a/tools/gpu/GrTest.cpp
+++ b/tools/gpu/GrTest.cpp
@@ -67,7 +67,8 @@
 #endif
         case kOpenGL_GrBackend: {
             GrGLTextureInfo* glInfo = (GrGLTextureInfo*)(handle);
-            return GrBackendTexture(width, height, config, mipMapped, *glInfo);
+            SkASSERT(glInfo->fFormat);
+            return GrBackendTexture(width, height, mipMapped, *glInfo);
         }
         case kMock_GrBackend: {
             GrMockTextureInfo* mockInfo = (GrMockTextureInfo*)(handle);