Inline hot ctor/dtors for struct-like gfx:: geometry types

ui/gfx/size_f.h

Index: ui/gfx/size_f.h
diff --git a/ui/gfx/size_f.h b/ui/gfx/size_f.h
index 98d2e0cc77fcb574eb37bae6d4f4e251ba5b9086..a38d3f6caffffd1e3eb4941f015bb0c32a4f70cc 100644
--- a/ui/gfx/size_f.h
+++ b/ui/gfx/size_f.h
@@ -16,9 +16,9 @@ namespace gfx {
 // A floating version of gfx::Size.
 class UI_EXPORT SizeF : public SizeBase<SizeF, float> {
  public:
-  SizeF();
-  SizeF(float width, float height);
-  ~SizeF();
+  SizeF() : SizeBase<SizeF, float>(0, 0) {}
+  SizeF(float width, float height) : SizeBase<SizeF, float>(width, height) {}
+  ~SizeF() {}
 
   void Scale(float scale) {
     Scale(scale, scale);