Turn ContextInfos returned by GrContextFactory into structs.

tests/GrTextureMipMapInvalidationTest.cpp

Index: tests/GrTextureMipMapInvalidationTest.cpp
diff --git a/tests/GrTextureMipMapInvalidationTest.cpp b/tests/GrTextureMipMapInvalidationTest.cpp
index 523bb82aaeac77205e55bf6e9026726c9550d9c0..e8f6bcce6a31df2351b14c3a890ef7b4082c14b0 100644
--- a/tests/GrTextureMipMapInvalidationTest.cpp
+++ b/tests/GrTextureMipMapInvalidationTest.cpp
@@ -20,7 +20,7 @@
 // Tests that GrSurface::asTexture(), GrSurface::asRenderTarget(), and static upcasting of texture
 // and render targets to GrSurface all work as expected.
 DEF_GPUTEST_FOR_NULLGL_CONTEXT(GrTextureMipMapInvalidationTest, reporter, ctxInfo) {
-    GrContext* context = ctxInfo.fGrContext;
+    GrContext* context = ctxInfo.grContext();
     GrSurfaceDesc desc;
     desc.fConfig = kSkia8888_GrPixelConfig;
     desc.fFlags = kRenderTarget_GrSurfaceFlag;