Re-adding red texture support (by rolling back r3800)

http://code.google.com/p/skia/source/detail?r=3622 - for original review
http://crbug.com/125596 ('M20 windows renderer stability maze') - for issue



git-svn-id: http://skia.googlecode.com/svn/trunk@3802 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/gl/GrGLCaps.h b/src/gpu/gl/GrGLCaps.h
index c5d1d05..eb09576 100644
--- a/src/gpu/gl/GrGLCaps.h
+++ b/src/gpu/gl/GrGLCaps.h
@@ -206,6 +206,9 @@
     /// Is there support for glTexStorage
     bool texStorageSupport() const { return fTexStorageSupport; }
 
+    /// Is there support for GL_RED and GL_R8
+    bool textureRedSupport() const { return fTextureRedSupport; }
+
 private:
     /**
      * Maintains a bit per GrPixelConfig. It is used to avoid redundantly
@@ -273,6 +276,7 @@
     bool fPackFlipYSupport : 1;
     bool fTextureUsageSupport : 1;
     bool fTexStorageSupport : 1;
+    bool fTextureRedSupport : 1;
 };
 
 #endif