Fix FP / header inconsistency

Bug: skia:
Change-Id: I99673d19ae7ce6dd7f781ffd58318e8abd524db9
Reviewed-on: https://skia-review.googlesource.com/c/168364
Commit-Queue: Brian Osman <brianosman@google.com>
Commit-Queue: Allan MacKinnon <allanmac@google.com>
Auto-Submit: Brian Osman <brianosman@google.com>
Reviewed-by: Allan MacKinnon <allanmac@google.com>

src/gpu/effects/GrRRectBlurEffect.fp

@@ -62,7 +62,8 @@ uniform half blurRadius;
 
             GrPaint paint;
 
-            rtc->clear(nullptr, 0x0, GrRenderTargetContext::CanClearFullscreen::kYes);
+            rtc->clear(nullptr, SK_PMColor4fTRANSPARENT,
+                       GrRenderTargetContext::CanClearFullscreen::kYes);
             rtc->drawRRect(GrNoClip(), std::move(paint), GrAA::kYes, SkMatrix::I(), rrectToDraw,
                            GrStyle::SimpleFill());