Work around for nexus 6 TexSubImage issue

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/c69fe20ef35df0776b179cbd5ce4d1bdc0ba4090

Review URL: https://codereview.chromium.org/1173203005
diff --git a/src/gpu/GrCaps.cpp b/src/gpu/GrCaps.cpp
index ba4e104..f2e88b0 100644
--- a/src/gpu/GrCaps.cpp
+++ b/src/gpu/GrCaps.cpp
@@ -109,6 +109,7 @@
     fSupressPrints = options.fSuppressPrints;
     fDrawPathMasksToCompressedTextureSupport = options.fDrawPathToCompressedTexture;
     fGeometryBufferMapThreshold = options.fGeometryBufferMapThreshold;
+    fUseDrawInsteadOfPartialRenderTargetWrite = options.fUseDrawInsteadOfPartialRenderTargetWrite;
 }
 
 void GrCaps::applyOptionsOverrides(const GrContextOptions& options) {
@@ -150,6 +151,8 @@
     r.appendf("Oversized Stencil Support          : %s\n", gNY[fOversizedStencilSupport]);
     r.appendf("Texture Barrier Support            : %s\n", gNY[fTextureBarrierSupport]);
     r.appendf("Draw Instead of Clear [workaround] : %s\n", gNY[fUseDrawInsteadOfClear]);
+    r.appendf("Draw Instead of TexSubImage [workaround] : %s\n",
+              gNY[fUseDrawInsteadOfPartialRenderTargetWrite]);
     if (this->advancedBlendEquationSupport()) {
         r.appendf("Advanced Blend Equation Blacklist  : 0x%x\n", fAdvBlendEqBlacklist);
     }