Add direct getter for GrCaps to GrContext.

tests/GrPorterDuffTest.cpp

Index: tests/GrPorterDuffTest.cpp
diff --git a/tests/GrPorterDuffTest.cpp b/tests/GrPorterDuffTest.cpp
index 314671200f3d04d1168c99fbc2fc94a4c2fe568e..41a8b5aa5911e1100411f843a0d2c5b4c37e9098 100644
--- a/tests/GrPorterDuffTest.cpp
+++ b/tests/GrPorterDuffTest.cpp
@@ -949,7 +949,7 @@ static void test_no_dual_source_blending(skiatest::Reporter* reporter) {
         return;
     }
 
-    const GrCaps& caps = *ctx->getGpu()->caps();
+    const GrCaps& caps = *ctx->caps();
     if (caps.shaderCaps()->dualSourceBlendingSupport()) {
         SkFAIL("Null context failed to honor request for no ARB_blend_func_extended.");
         return;