Pass gfx structs by const ref (gfx::Vector2d/F)

ui/events/gesture_detection/velocity_tracker_unittest.cc

 // Copyright 2014 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 "base/basictypes.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/events/gesture_detection/velocity_tracker_state.h"
@@ skipping 32 matching lines @@
 
 class VelocityTrackerTest : public testing::Test {
  public:
   VelocityTrackerTest() {}
   ~VelocityTrackerTest() override {}
 
  protected:
   static MockMotionEvent Sample(MotionEvent::Action action,
                                 const gfx::PointF& p0,
                                 TimeTicks t0,
-                                gfx::Vector2dF v,
+                                const gfx::Vector2dF& v,
                                 TimeDelta dt) {
     const gfx::PointF p = p0 + ScaleVector2d(v, dt.InSecondsF());
     return MockMotionEvent(action, t0 + dt, p.x(), p.y());
   }
 
   static void ApplyMovementSequence(VelocityTrackerState* state,
                                     const gfx::PointF& p0,
-                                    gfx::Vector2dF v,
+                                    const gfx::Vector2dF& v,
                                     TimeTicks t0,
                                     TimeDelta t,
                                     size_t samples) {
     EXPECT_TRUE(!!samples);
     if (!samples)
       return;
     const base::TimeDelta dt = t / samples;
     state->AddMovement(Sample(MotionEvent::ACTION_DOWN, p0, t0, v, dt * 0));
     ApplyMovement(state, p0, v, t0, t, samples);
     state->AddMovement(Sample(MotionEvent::ACTION_UP, p0, t0, v, t));
   }
 
   static void ApplyMovement(VelocityTrackerState* state,
                             const gfx::PointF& p0,
-                            gfx::Vector2dF v,
+                            const gfx::Vector2dF& v,
                             TimeTicks t0,
                             TimeDelta t,
                             size_t samples) {
     EXPECT_TRUE(!!samples);
     if (!samples)
       return;
     const base::TimeDelta dt = t / samples;
     for (size_t i = 0; i < samples; ++i)
       state->AddMovement(Sample(MotionEvent::ACTION_MOVE, p0, t0, v, dt * i));
   }
@@ skipping 166 matching lines @@
 
   // This does not hold for the unrestricted LSQ2 strategy.
   state_unrestricted.ComputeCurrentVelocity(1000, 20000);
   EXPECT_EQ(0, state_unrestricted.GetXVelocity(0));
   // Y velocity is negative, despite the fact that the finger only moved in the
   // positive y direction.
   EXPECT_GT(0, state_unrestricted.GetYVelocity(0));
 }
 
 }  // namespace ui