Add Make[backend] calls for creating GrContexts

Docs-Preview: https://skia.org/?cl=26369
Bug: skia:
Change-Id: I460ee63e466f85b05918479f068a2e5ca2d70550
Reviewed-on: https://skia-review.googlesource.com/26369
Commit-Queue: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/samplecode/SampleApp.cpp b/samplecode/SampleApp.cpp
index 1676fc3..c36e2e8 100644
--- a/samplecode/SampleApp.cpp
+++ b/samplecode/SampleApp.cpp
@@ -276,8 +276,7 @@
         }
 
         SkASSERT(nullptr == fCurContext);
-        fCurContext = GrContext::Create(kOpenGL_GrBackend, (GrBackendContext) fCurIntf,
-                                        backendOptions.fGrContextOptions);
+        fCurContext = GrContext::MakeGL(fCurIntf, backendOptions.fGrContextOptions).release();
 
         if (nullptr == fCurContext || nullptr == fCurIntf) {
             // We need some context and interface to see results