Move SkGLContext and some GrGLInterface implementations to skgputest module

BUG=skia:
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Committed: https://skia.googlesource.com/skia/+/fe3456cb006110d045b26ff3f8681b893a757b58

Review URL: https://codereview.chromium.org/1815823002
diff --git a/tools/skiaserve/Request.h b/tools/skiaserve/Request.h
index e3bc373..d19c2ba 100644
--- a/tools/skiaserve/Request.h
+++ b/tools/skiaserve/Request.h
@@ -19,7 +19,9 @@
 
 #include "UrlDataManager.h"
 
+namespace sk_gpu_test {
 class GrContextFactory;
+}
 struct MHD_Connection;
 struct MHD_PostProcessor;
 
@@ -69,7 +71,7 @@
     GrContext* getContext();
 
     sk_sp<SkPicture> fPicture;
-    GrContextFactory* fContextFactory;
+    sk_gpu_test::GrContextFactory* fContextFactory;
     SkAutoTUnref<SkSurface> fSurface;
     bool fGPUEnabled;
 };