fix printing of error messages in canvasstatetest.

tests/CanvasStateTest.cpp

 
 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Test.h"
 #include "SkBitmapDevice.h"
 #include "SkCanvas.h"
 #include "SkCanvasStateUtils.h"
 #include "SkDrawFilter.h"
+#include "SkError.h"
 #include "SkPaint.h"
 #include "SkRect.h"
 #include "SkRRect.h"
 
 static void test_complex_layers(skiatest::Reporter* reporter) {
     const int WIDTH = 400;
     const int HEIGHT = 400;
     const int SPACER = 10;
 
     SkRect rect = SkRect::MakeXYWH(SkIntToScalar(SPACER), SkIntToScalar(SPACER),
@@ skipping 174 matching lines @@
 
     REPORTER_ASSERT(reporter, NULL != canvas.getDrawFilter());
     REPORTER_ASSERT(reporter, NULL == tmpCanvas->getDrawFilter());
 
     tmpCanvas->unref();
     SkCanvasStateUtils::ReleaseCanvasState(state);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
+// we need this function to prevent SkError from printing to stdout
+static void error_callback(SkError code, void* ctx) {}
+
 static void test_soft_clips(skiatest::Reporter* reporter) {
     SkBitmapDevice device(SkBitmap::kARGB_8888_Config, 10, 10);
     SkCanvas canvas(&device);
 
     SkRRect roundRect;
     roundRect.setOval(SkRect::MakeWH(5, 5));
 
     canvas.clipRRect(roundRect, SkRegion::kIntersect_Op, true);
 
+    SkSetErrorCallback(error_callback, NULL);
+
     SkCanvasState* state = SkCanvasStateUtils::CaptureCanvasState(&canvas);
     REPORTER_ASSERT(reporter, !state);
+
+    REPORTER_ASSERT(reporter, kInvalidOperation_SkError == SkGetLastError());
+    SkClearLastError();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 
 static void test_canvas_state_utils(skiatest::Reporter* reporter) {
     test_complex_layers(reporter);
     test_complex_clips(reporter);
     test_draw_filters(reporter);
     test_soft_clips(reporter);
 }
 
 #include "TestClassDef.h"
 DEFINE_TESTCLASS("CanvasState", TestCanvasStateClass, test_canvas_state_utils)