Update SkSurface MakeFromBackend* factories to take an SkColorType.

Bug: skia:
Change-Id: Ib1b03b1181ec937843eac2e8d8cb03ebe53e32c1
Reviewed-on: https://skia-review.googlesource.com/86760
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/gl/GrGLRenderTarget.cpp b/src/gpu/gl/GrGLRenderTarget.cpp
index 3aa632c..443128d 100644
--- a/src/gpu/gl/GrGLRenderTarget.cpp
+++ b/src/gpu/gl/GrGLRenderTarget.cpp
@@ -82,6 +82,15 @@
     return sk_sp<GrGLRenderTarget>(new GrGLRenderTarget(gpu, desc, idDesc, sb));
 }
 
+GrBackendRenderTarget GrGLRenderTarget::getBackendRenderTarget() const {
+    GrGLFramebufferInfo fbi;
+    fbi.fFBOID = fRTFBOID;
+    fbi.fFormat = this->getGLGpu()->glCaps().configSizedInternalFormat(this->config());
+
+    return GrBackendRenderTarget(this->width(), this->height(), this->numColorSamples(),
+                                 this->numStencilSamples(), fbi);
+}
+
 size_t GrGLRenderTarget::onGpuMemorySize() const {
     return GrSurface::ComputeSize(this->config(), this->width(), this->height(),
                                   fNumSamplesOwnedPerPixel, GrMipMapped::kNo);