Loosen requirement that there be only one GrDrawTarget

src/gpu/GrRenderTarget.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "GrRenderTarget.h"
 
 #include "GrContext.h"
 #include "GrDrawContext.h"
+#include "GrDrawTarget.h"
 #include "GrGpu.h"
 #include "GrRenderTargetPriv.h"
 #include "GrStencilAttachment.h"
 
 void GrRenderTarget::discard() {
     // go through context so that all necessary flushing occurs
     GrContext* context = this->getContext();
     if (!context) {
         return;
     }
@@ skipping 25 matching lines @@
         fResolveRect.setLargestInverted();
     } else {
         if (!fResolveRect.intersect(0, 0, this->width(), this->height())) {
             fResolveRect.setLargestInverted();
         }
     }
 }
 
 void GrRenderTarget::onRelease() {
     SkSafeSetNull(fStencilAttachment);
+    fLastDrawTarget = nullptr;
 
     INHERITED::onRelease();
 }
 
 void GrRenderTarget::onAbandon() {
     SkSafeSetNull(fStencilAttachment);
+    fLastDrawTarget = nullptr;
 
     INHERITED::onAbandon();
 }
 
+void GrRenderTarget::setLastDrawTarget(GrDrawTarget* dt) {
+    if (fLastDrawTarget) {
+        SkASSERT(fLastDrawTarget->isClosed());
+    }
+
+    fLastDrawTarget = dt;
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 bool GrRenderTargetPriv::attachStencilAttachment(GrStencilAttachment* stencil) {
     if (!stencil && !fRenderTarget->fStencilAttachment) {
         // No need to do any work since we currently don't have a stencil attachment and
         // we're not acctually adding one.
         return true;
     }
     fRenderTarget->fStencilAttachment = stencil;
     if (!fRenderTarget->completeStencilAttachment()) {
         SkSafeSetNull(fRenderTarget->fStencilAttachment);
         return false;
     } 
     return true;
 }