Relanding 7914



git-svn-id: http://skia.googlecode.com/svn/trunk@7940 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp
index 65f3e0f..4722e68 100644
--- a/src/gpu/GrContext.cpp
+++ b/src/gpu/GrContext.cpp
@@ -433,6 +433,11 @@
         desc.fHeight = GrMax(MIN_SIZE, GrNextPow2(desc.fHeight));
     }
 
+    // Renderable A8 targets are not universally supported (e.g., not on ANGLE)
+    GrAssert(this->isConfigRenderable(kAlpha_8_GrPixelConfig) ||
+             !(desc.fFlags & kRenderTarget_GrTextureFlagBit) ||
+             (desc.fConfig != kAlpha_8_GrPixelConfig));
+
     GrResource* resource = NULL;
     int origWidth = desc.fWidth;
     int origHeight = desc.fHeight;
@@ -1473,7 +1478,10 @@
                 }
                 swapRAndB = false; // we will handle the swap in the draw.
 
-                GrDrawTarget::AutoStateRestore asr(fGpu, GrDrawTarget::kReset_ASRInit);
+                // We protect the existing geometry here since it may not be
+                // clear to the caller that a draw operation (i.e., drawSimpleRect)
+                // can be invoked in this method
+                GrDrawTarget::AutoGeometryAndStatePush agasp(fGpu, GrDrawTarget::kReset_ASRInit);
                 GrDrawState* drawState = fGpu->drawState();
                 GrAssert(effect);
                 drawState->setEffect(0, effect);
@@ -1660,7 +1668,10 @@
         return false;
     }
 
-    GrDrawTarget::AutoStateRestore  asr(fGpu, GrDrawTarget::kReset_ASRInit);
+    // writeRenderTargetPixels can be called in the midst of drawing another
+    // object (e.g., when uploading a SW path rendering to the gpu while 
+    // drawing a rect) so preserve the current geometry.
+    GrDrawTarget::AutoGeometryAndStatePush agasp(fGpu, GrDrawTarget::kReset_ASRInit);
     GrDrawState* drawState = fGpu->drawState();
     GrAssert(effect);
     drawState->setEffect(0, effect);