Add Vector2d classes that represent offsets, instead of using Point.

ui/gfx/size_unittest.cc

Index: ui/gfx/size_unittest.cc
diff --git a/ui/gfx/size_unittest.cc b/ui/gfx/size_unittest.cc
index 4a281ed42eacb2f0a1cfb1e596caf0153cef18c2..9dfcb424bdf4959eb8869b273b5882896ac4ba7f 100644
--- a/ui/gfx/size_unittest.cc
+++ b/ui/gfx/size_unittest.cc
@@ -4,6 +4,7 @@
 
 #include "ui/gfx/size_base.h"
 
+#include "base/basictypes.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/gfx/size.h"
 #include "ui/gfx/size_conversions.h"
@@ -136,4 +137,42 @@ TEST(SizeTest, ToRoundedSize) {
             gfx::ToRoundedSize(gfx::SizeF(-10.9999f, -10.9999f)));
 }
 
+TEST(SizeTest, SizeOfVector) {
+  int int_tests[][2] = {
+    { 0, 0 },
+    { 0, -1 },
+    { -1, 0 },
+    { 1, -1 },
+    { 1, 1 },
+    { -1, 1 },
+    { -1, -1 }
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(int_tests); ++i) {
+    int abs0 = std::abs(int_tests[i][0]);
+    int abs1 = std::abs(int_tests[i][1]);
+    gfx::Size expected(abs0, abs1);
+    gfx::Vector2d vector(int_tests[i][0], int_tests[i][1]);
+    EXPECT_EQ(expected.ToString(), SizeOfVector2d(vector).ToString());
+  }
+
+  float float_tests[][2] = {
+    { 0, 0 },
+    { 0, -0.1f },
+    { -0.1f, 0 },
+    { 0.1f, -0.1f },
+    { 0.1f, 0.1f },
+    { -0.1f, 0.1f },
+    { -0.1f, -0.1f }
+  };
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(float_tests); ++i) {
+    float abs0 = std::abs(float_tests[i][0]);
+    float abs1 = std::abs(float_tests[i][1]);
+    gfx::SizeF expected(abs0, abs1);
+    gfx::Vector2dF vector(float_tests[i][0], float_tests[i][1]);
+    EXPECT_EQ(expected.ToString(), SizeOfVector2d(vector).ToString());
+  }
+}
+
 }  // namespace ui