Restructure flushing relationship between GrContext, GrDrawingManager, and GrResourceCache.

src/gpu/GrDrawingManager.h

Index: src/gpu/GrDrawingManager.h
diff --git a/src/gpu/GrDrawingManager.h b/src/gpu/GrDrawingManager.h
index 745820f439b62ff2db98a3e9d5edb4c194faba8b..5faf747f3297fa2d79f37194644e66b7c0b5938c 100644
--- a/src/gpu/GrDrawingManager.h
+++ b/src/gpu/GrDrawingManager.h
@@ -13,6 +13,7 @@
 #include "GrBatchFlushState.h"
 #include "GrPathRendererChain.h"
 #include "GrPathRenderer.h"
+#include "GrResourceCache.h"
 #include "SkTDArray.h"
 
 class GrContext;
@@ -49,6 +50,12 @@ public:
                                     GrPathRendererChain::DrawType drawType,
                                     GrPathRenderer::StencilSupport* stencilSupport = NULL);
 
+    void flushIfNecessary() {

[robertphillips, 2016/09/02 16:23:06]

What happened to "this->caps()->immediateFlush()" ?

+        if (fContext->getResourceCache()->requestsFlush()) {
+            this->internalFlush(GrResourceCache::kCacheRequested);
+        }
+    }
+
     static bool ProgramUnitTest(GrContext* context, int maxStages);
 
 private:
@@ -68,8 +75,8 @@ private:
     void abandon();
     void cleanup();
     void reset();
-    /** Returns true if there was anything to flush and false otherwise */
-    bool flush();
+    void flush() { this->internalFlush(GrResourceCache::FlushType::kExternal); }
+    void internalFlush(GrResourceCache::FlushType);
 
     friend class GrContext;  // for access to: ctor, abandon, reset & flush