Fix overflow/underflow in gfx geometry once and for all

ui/gfx/geometry/size.cc

Index: ui/gfx/geometry/size.cc
diff --git a/ui/gfx/geometry/size.cc b/ui/gfx/geometry/size.cc
index 7cda8e1814cb6139b03ed68d65b07cea5513747e..33f5de17c353d85a2e2136155015cc2910a17c27 100644
--- a/ui/gfx/geometry/size.cc
+++ b/ui/gfx/geometry/size.cc
@@ -15,6 +15,7 @@
 #include "base/numerics/safe_math.h"
 #include "base/strings/stringprintf.h"
 #include "build/build_config.h"
+#include "ui/gfx/geometry/safe_integer_conversions.h"
 #include "ui/gfx/geometry/size_conversions.h"
 
 namespace gfx {
@@ -56,7 +57,7 @@ base::CheckedNumeric<int> Size::GetCheckedArea() const {
 }
 
 void Size::Enlarge(int grow_width, int grow_height) {
-  SetSize(width() + grow_width, height() + grow_height);
+  SetSize(SafeAdd(width(), grow_width), SafeAdd(height(), grow_height));
 }
 
 void Size::SetToMin(const Size& other) {