Fixes for nonmodal pinch zoom.

cc/layer_tree_host_impl_unittest.cc

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/layer_tree_host_impl.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 628 matching lines @@
         EXPECT_EQ(scrollInfo->pageScaleDelta, minPageScale);
 
         if (!m_hostImpl->settings().pageScalePinchZoomEnabled) {
             // Pushed to (0,0) via clamping against contents layer size.
             expectContains(*scrollInfo, scrollLayer->id(), gfx::Vector2d(-50, -50));
         } else {
             EXPECT_TRUE(scrollInfo->scrolls.empty());
         }
     }
 
-    // Two-finger panning
+    // Two-finger panning should not happen based on pinch events only
     {
         m_hostImpl->setPageScaleFactorAndLimits(1, minPageScale, maxPageScale);
         scrollLayer->setImplTransform(identityScaleTransform);
         scrollLayer->setScrollDelta(gfx::Vector2d());
         scrollLayer->setScrollOffset(gfx::Vector2d(20, 20));
 
         float pageScaleDelta = 1;
         m_hostImpl->pinchGestureBegin();
         m_hostImpl->pinchGestureUpdate(pageScaleDelta, gfx::Point(10, 10));
         m_hostImpl->pinchGestureUpdate(pageScaleDelta, gfx::Point(20, 20));
         m_hostImpl->pinchGestureEnd();
 
         scoped_ptr<ScrollAndScaleSet> scrollInfo = m_hostImpl->processScrollDeltas();
         EXPECT_EQ(scrollInfo->pageScaleDelta, pageScaleDelta);
+        EXPECT_TRUE(scrollInfo->scrolls.empty());
+    }
+
+    // Two-finger panning should work with interleaved scroll events
+    {
+        m_hostImpl->setPageScaleFactorAndLimits(1, minPageScale, maxPageScale);
+        scrollLayer->setImplTransform(identityScaleTransform);
+        scrollLayer->setScrollDelta(gfx::Vector2d());
+        scrollLayer->setScrollOffset(gfx::Vector2d(20, 20));
+
+        float pageScaleDelta = 1;
+        m_hostImpl->scrollBegin(gfx::Point(10, 10), InputHandlerClient::Wheel);
+        m_hostImpl->pinchGestureBegin();
+        m_hostImpl->pinchGestureUpdate(pageScaleDelta, gfx::Point(10, 10));
+        m_hostImpl->scrollBy(gfx::Point(10, 10), gfx::Vector2d(-10, -10));
+        m_hostImpl->pinchGestureUpdate(pageScaleDelta, gfx::Point(20, 20));
+        m_hostImpl->pinchGestureEnd();
+        m_hostImpl->scrollEnd();
+
+        scoped_ptr<ScrollAndScaleSet> scrollInfo = m_hostImpl->processScrollDeltas();
+        EXPECT_EQ(scrollInfo->pageScaleDelta, pageScaleDelta);
         expectContains(*scrollInfo, scrollLayer->id(), gfx::Vector2d(-10, -10));
     }
 }
 
 TEST_P(LayerTreeHostImplTest, pageScaleAnimation)
 {
     setupScrollAndContentsLayers(gfx::Size(100, 100));
     m_hostImpl->setViewportSize(gfx::Size(50, 50), gfx::Size(50, 50));
     initializeRendererAndDrawFrame();
 
@@ skipping 3774 matching lines @@
         testCaseIndex++;
     }
 }
 
 INSTANTIATE_TEST_CASE_P(LayerTreeHostImplTests,
                         LayerTreeHostImplTest,
                         ::testing::Values(false, true));
 
 }  // namespace
 }  // namespace cc