Make GrDrawTarget::Caps ref counted and GrGLCaps derive from it.

Also rename GrDrawTarget::getCaps() -> GrDrawTarget::caps().
Review URL: https://codereview.chromium.org/12843026

git-svn-id: http://skia.googlecode.com/svn/trunk@8364 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrTexture.cpp b/src/gpu/GrTexture.cpp
index 1e30661..479d7bb 100644
--- a/src/gpu/GrTexture.cpp
+++ b/src/gpu/GrTexture.cpp
@@ -136,7 +136,7 @@
                                                const GrTextureDesc& desc) {
     GrResourceKey::ResourceFlags flags = 0;
     bool tiled = NULL != params && params->isTiled();
-    if (tiled && !gpu->getCaps().npotTextureTileSupport()) {
+    if (tiled && !gpu->caps()->npotTextureTileSupport()) {
         if (!GrIsPow2(desc.fWidth) || !GrIsPow2(desc.fHeight)) {
             flags |= kStretchToPOT_TextureFlag;
             if (params->isBilerp()) {