Make some GrSurfaceProxy and GrTextureProxy methods easier to access

Move peek[Surface|Texture|RenderTarget]() from GrSurfaceProxyPriv to
to GrSurfaceProxy.

Move proxyMipMapped(), textureType(), and hasRestrictedSampling()
from GrTextureProxyPriv to GrTextureProxy.

Change-Id: I259114d0508c4613d55f7f1faccac362fa6fb281
Reviewed-on: https://skia-review.googlesource.com/144641
Commit-Queue: Robert Phillips <robertphillips@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/gl/GrGLProgram.cpp b/src/gpu/gl/GrGLProgram.cpp
index a392bc2..6bffe56 100644
--- a/src/gpu/gl/GrGLProgram.cpp
+++ b/src/gpu/gl/GrGLProgram.cpp
@@ -149,7 +149,7 @@
 
 void GrGLProgram::setRenderTargetState(const GrPrimitiveProcessor& primProc,
                                        const GrRenderTargetProxy* proxy) {
-    GrRenderTarget* rt = proxy->priv().peekRenderTarget();
+    GrRenderTarget* rt = proxy->peekRenderTarget();
     // Load the RT height uniform if it is needed to y-flip gl_FragCoord.
     if (fBuiltinUniformHandles.fRTHeightUni.isValid() &&
         fRenderTargetState.fRenderTargetSize.fHeight != rt->height()) {