Fix common axes logic to detect negated axes as not common

third_party/WebKit/Source/platform/transforms/RotationTest.cpp

 // Copyright 2016 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 "platform/transforms/Rotation.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
@@ skipping 40 matching lines @@
   EXPECT_TRUE(Rotation::getCommonAxis(Rotation(FloatPoint3D(1, 2, 3), 50),
                                       Rotation(FloatPoint3D(2, 4, 6), 100),
                                       axis, angleA, angleB));
   EXPECT_EQ(FloatPoint3D(1, 2, 3), axis);
   EXPECT_EQ(50, angleA);
   EXPECT_EQ(100, angleB);
 
   EXPECT_FALSE(Rotation::getCommonAxis(Rotation(FloatPoint3D(1, 2, 3), 50),
                                        Rotation(FloatPoint3D(3, 2, 1), 100),
                                        axis, angleA, angleB));
+
+  EXPECT_FALSE(Rotation::getCommonAxis(Rotation(FloatPoint3D(1, 2, 3), 50),
+                                       Rotation(FloatPoint3D(-1, -2, -3), 100),
+                                       axis, angleA, angleB));
 }
 
 }  // namespace blink