Sync the entire blend state before drawing in RendererGL.

BUG=angleproject:883

Change-Id: I903090c1a7ba90bd479ad8d24f943672eb51054e
Reviewed-on: https://chromium-review.googlesource.com/266033
Reviewed-by: Brandon Jones <bajones@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/State.cpp b/src/libANGLE/State.cpp
index e727cd5..9132b16 100644
--- a/src/libANGLE/State.cpp
+++ b/src/libANGLE/State.cpp
@@ -431,12 +431,14 @@
     mSampleCoverageInvert = invert;
 }
 
-void State::getSampleCoverageParams(GLclampf *value, bool *invert) const
+GLclampf State::getSampleCoverageValue() const
 {
-    ASSERT(value != NULL && invert != NULL);
+    return mSampleCoverageValue;
+}
 
-    *value = mSampleCoverageValue;
-    *invert = mSampleCoverageInvert;
+bool State::getSampleCoverageInvert() const
+{
+    return mSampleCoverageInvert;
 }
 
 bool State::isScissorTestEnabled() const