Push setMipColorMode calls further down-stack & add to GrTextureProxy

setMipColorMode seems like an odd call. 

Change-Id: I24a1ac3883d52499f3be27282d006144d15b26f1
Reviewed-on: https://skia-review.googlesource.com/9725
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
diff --git a/include/private/GrTextureProxy.h b/include/private/GrTextureProxy.h
index 9383ec7..ee954dc 100644
--- a/include/private/GrTextureProxy.h
+++ b/include/private/GrTextureProxy.h
@@ -24,6 +24,8 @@
     // Actually instantiate the backing texture, if necessary
     GrTexture* instantiate(GrResourceProvider*);
 
+    void setMipColorMode(SkDestinationSurfaceColorMode colorMode);
+
 protected:
     friend class GrSurfaceProxy; // for ctors
 
@@ -37,7 +39,7 @@
     size_t onGpuMemorySize() const override;
 
     // For wrapped proxies the GrTexture pointer is stored in GrIORefProxy.
-    // For deferred proxies that pointer will be filled n when we need to instantiate
+    // For deferred proxies that pointer will be filled in when we need to instantiate
     // the deferred resource
 
     typedef GrSurfaceProxy INHERITED;