Add query for whether or not we have compressedTexSubImage

src/gpu/GrDrawTargetCaps.h

Index: src/gpu/GrDrawTargetCaps.h
diff --git a/src/gpu/GrDrawTargetCaps.h b/src/gpu/GrDrawTargetCaps.h
index b979b534c40528d083f24feec908fae5c714b812..1a3a84cf2807c32f1a71d2ffe475e56f9909c816 100644
--- a/src/gpu/GrDrawTargetCaps.h
+++ b/src/gpu/GrDrawTargetCaps.h
@@ -40,6 +40,7 @@ public:
     bool dstReadInShaderSupport() const { return fDstReadInShaderSupport; }
     bool discardRenderTargetSupport() const { return fDiscardRenderTargetSupport; }
     bool gpuTracingSupport() const { return fGpuTracingSupport; }
+    bool compressedTexSubImageSupport() const { return fCompressedTexSubImageSupport; }
 
     /**
      * Indicates whether GPU->CPU memory mapping for GPU resources such as vertex buffers and
@@ -90,6 +91,7 @@ protected:
     bool fDiscardRenderTargetSupport: 1;
     bool fReuseScratchTextures      : 1;
     bool fGpuTracingSupport         : 1;
+    bool fCompressedTexSubImageSupport : 1;
 
     uint32_t fMapBufferFlags;