Revert "Have a GrBackendFormat be stored on gpu proxies."

This reverts commit 51b1c12bbc2fa3f8d4faa29ad19c6f3cb34837ce.

Reason for revert: reverting till flutter gets to 1.1 to fix build issues.

Original change's description:
> Have a GrBackendFormat be stored on gpu proxies.
>
> Bug: skia:
> Change-Id: Iaf1fb24ab29a61d44e5fa59a5e0867ed02dcda90
> Reviewed-on: https://skia-review.googlesource.com/c/168021
> Reviewed-by: Brian Osman <brianosman@google.com>
> Commit-Queue: Greg Daniel <egdaniel@google.com>

TBR=egdaniel@google.com,bsalomon@google.com,brianosman@google.com

Change-Id: I574fdc084ef5994596c51fb0d60423b5dc01b885
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:903701 chromium:903756
Reviewed-on: https://skia-review.googlesource.com/c/169835
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index a29336e..daa86fc 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -164,12 +164,10 @@
     if (kUnknown_GrPixelConfig == config) {
         return nullptr;
     }
-    GrBackendFormat format =
-            context->contextPriv().caps()->getBackendFormatFromColorType(origInfo.colorType());
     // This method is used to create SkGpuDevice's for SkSurface_Gpus. In this case
     // they need to be exact.
     return context->contextPriv().makeDeferredRenderTargetContext(
-                                    format, SkBackingFit::kExact,
+                                    SkBackingFit::kExact,
                                     origInfo.width(), origInfo.height(),
                                     config, origInfo.refColorSpace(), sampleCount,
                                     mipMapped, origin, surfaceProps, budgeted);
@@ -1751,21 +1749,14 @@
                                                             : SkBackingFit::kExact;
 
     GrPixelConfig config = fRenderTargetContext->colorSpaceInfo().config();
-    const GrBackendFormat& origFormat = fRenderTargetContext->asSurfaceProxy()->backendFormat();
-    GrBackendFormat format = origFormat.makeTexture2D();
-    if (!format.isValid()) {
-        return nullptr;
-    }
     if (kRGBA_1010102_GrPixelConfig == config) {
         // If the original device is 1010102, fall back to 8888 so that we have a usable alpha
         // channel in the layer.
         config = kRGBA_8888_GrPixelConfig;
-        format =
-            fContext->contextPriv().caps()->getBackendFormatFromColorType(kRGBA_8888_SkColorType);
     }
 
     sk_sp<GrRenderTargetContext> rtc(fContext->contextPriv().makeDeferredRenderTargetContext(
-            format, fit, cinfo.fInfo.width(), cinfo.fInfo.height(), config,
+            fit, cinfo.fInfo.width(), cinfo.fInfo.height(), config,
             fRenderTargetContext->colorSpaceInfo().refColorSpace(),
             fRenderTargetContext->numStencilSamples(), GrMipMapped::kNo,
             kBottomLeft_GrSurfaceOrigin, &props));