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

ui/gfx/point_base.h

Index: ui/gfx/point_base.h
diff --git a/ui/gfx/point_base.h b/ui/gfx/point_base.h
index 2eed6142d6c3b1a3999d88bf6b7e720118624966..870b2644e4f986bc1d99fbad30e80bbc094eae80 100644
--- a/ui/gfx/point_base.h
+++ b/ui/gfx/point_base.h
@@ -41,6 +41,16 @@ class UI_EXPORT PointBase {
     Offset(-vector.x(), -vector.y());
   }
 
+  void ClampToMax(const Class& max) {
+    x_ = x_ <= max.x_ ? x_ : max.x_;
+    y_ = y_ <= max.y_ ? y_ : max.y_;
+  }
+
+  void ClampToMin(const Class& min) {
+    x_ = x_ >= min.x_ ? x_ : min.x_;
+    y_ = y_ >= min.y_ ? y_ : min.y_;
+  }
+
   Class Middle(const Class& other) const WARN_UNUSED_RESULT {
     return Class((x_ + other.x_) / 2, (y_ + other.y_) / 2);
   }