Fix cases of variable shadowing in /src/gpu.

If we manage to fix all the existing cases of variable shadowing, we
could enable -Wshadow.

Change-Id: I3ad3c603f97e398382202d11c159d25cca0a7b9f
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/438317
Commit-Queue: John Stiles <johnstiles@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/GrSoftwarePathRenderer.cpp b/src/gpu/GrSoftwarePathRenderer.cpp
index b32dbe5..ec47bc3 100644
--- a/src/gpu/GrSoftwarePathRenderer.cpp
+++ b/src/gpu/GrSoftwarePathRenderer.cpp
@@ -315,10 +315,9 @@
         args.fShape->writeUnstyledKey(&builder[7]);
     }
 
-    sk_sp<GrTextureProxy> proxy;
     GrSurfaceProxyView view;
     if (useCache) {
-        auto proxy = fProxyProvider->findOrCreateProxyByUniqueKey(maskKey);
+        sk_sp<GrTextureProxy> proxy = fProxyProvider->findOrCreateProxyByUniqueKey(maskKey);
         if (proxy) {
             GrSwizzle swizzle = args.fSurfaceDrawContext->caps()->getReadSwizzle(
                     proxy->backendFormat(), GrColorType::kAlpha_8);