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

Previously Point served two purposes, to be a position in 2d space, and also
an offset from the origin. This introduces a Vector2d class to represent an
offset, allowing typesafety checks for geometric operations.

The following are now the case:

Point +/- Vector = Point
- A point plus/minus an offset gives you a point at a position offset by the
vector.

Vector +/- Vector = Vector
- Two offsets can be added together to make a new offset.

Point - Point = Vector
- Subtracting one point from another gives you the offset between the two
points.

We add some new methods to perform these operations:

Rect::OffsetFromOrigin() gives the offset between the position of the rect
and the origin.

Point::OffsetFromOrigin() gives the offset between the point and the origin.

PointAtOffsetFromOrigin(Vector2d) converts a Vector2d to a Point at the given
offset away from the origin.

Rect::Offset(), Point::Add(), and Point::Subtract() now receive a Vector2d
instead of a point.

BUG=147395
R=sky

Review URL: https://codereview.chromium.org/11269022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@165198 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 1 insertions, 1 deletions

diff --git a/ui/views/painter.cc b/ui/views/painter.cc
index 4275c54..99c537c 100644
--- a/ui/views/painter.cc
+++ b/ui/views/painter.cc
@@ -171,7 +171,7 @@ void Painter::PaintPainterAt(gfx::Canvas* canvas,
                              const gfx::Rect& rect) {
   DCHECK(canvas && painter);
   canvas->Save();
-  canvas->Translate(rect.origin());
+  canvas->Translate(rect.OffsetFromOrigin());
   painter->Paint(canvas, rect.size());
   canvas->Restore();
 }