Revert "Move resourceProvider accessor to GrContextPriv"

This reverts commit 1f9ed8501b0007846b3032f4bfc38aee98c175a1.

Reason for revert: 
 1. breaking android roll 
 2. breaking Build-Debian9-Clang-arm-Release-Android_API26



Original change's description:
> Move resourceProvider accessor to GrContextPriv
> 
> Change-Id: I5cddd620a7ec4b006b7359864ede58e9d4dd684e
> Reviewed-on: https://skia-review.googlesource.com/94340
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Robert Phillips <robertphillips@google.com>

TBR=egdaniel@google.com,bsalomon@google.com,robertphillips@google.com

Change-Id: I20b2d267c0925f20453b635663654967199a1197
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/94964
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>
diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp
index c13cd53..95d2344 100644
--- a/src/gpu/GrContext.cpp
+++ b/src/gpu/GrContext.cpp
@@ -484,7 +484,7 @@
     ASSERT_OWNED_PROXY_PRIV(dst->asSurfaceProxy());
     GR_CREATE_TRACE_MARKER_CONTEXT("GrContextPriv", "writeSurfacePixels", fContext);
 
-    if (!dst->asSurfaceProxy()->instantiate(this->resourceProvider())) {
+    if (!dst->asSurfaceProxy()->instantiate(fContext->resourceProvider())) {
         return false;
     }
 
@@ -563,7 +563,7 @@
             return false;
         }
 
-        if (!tempProxy->instantiate(this->resourceProvider())) {
+        if (!tempProxy->instantiate(fContext->resourceProvider())) {
             return false;
         }
         GrTexture* texture = tempProxy->priv().peekTexture();
@@ -616,7 +616,7 @@
     GR_CREATE_TRACE_MARKER_CONTEXT("GrContextPriv", "readSurfacePixels", fContext);
 
     // MDB TODO: delay this instantiation until later in the method
-    if (!src->asSurfaceProxy()->instantiate(this->resourceProvider())) {
+    if (!src->asSurfaceProxy()->instantiate(fContext->resourceProvider())) {
         return false;
     }
 
@@ -724,7 +724,7 @@
         configToRead = tempDrawInfo.fReadConfig;
     }
 
-    if (!proxyToRead->instantiate(this->resourceProvider())) {
+    if (!proxyToRead->instantiate(fContext->resourceProvider())) {
         return false;
     }