ui: Add methods to clamp Sizes, Points, and Vectors from above or below.

ui/gfx/vector3d_f.h

Index: ui/gfx/vector3d_f.h
diff --git a/ui/gfx/vector3d_f.h b/ui/gfx/vector3d_f.h
index a2845f89267880e28b4634df450471e30c520402..49ec90872d9a1f45f9222c944345705642c0baf1 100644
--- a/ui/gfx/vector3d_f.h
+++ b/ui/gfx/vector3d_f.h
@@ -44,6 +44,18 @@ class UI_EXPORT Vector3dF {
   void operator+=(const Vector3dF& other) { Add(other); }
   void operator-=(const Vector3dF& other) { Subtract(other); }
 
+  void ClampFromAbove(const Vector3dF& other) {
+    x_ = x_ <= other.x_ ? x_ : other.x_;
+    y_ = y_ <= other.y_ ? y_ : other.y_;
+    z_ = z_ <= other.z_ ? z_ : other.z_;
+  }
+
+  void ClampFromBelow(const Vector3dF& other) {
+    x_ = x_ >= other.x_ ? x_ : other.x_;
+    y_ = y_ >= other.y_ ? y_ : other.y_;
+    z_ = z_ >= other.z_ ? z_ : other.z_;
+  }
+
   // Gives the square of the diagonal length of the vector.
   double LengthSquared() const;
   // Gives the diagonal length of the vector.