Make PageSizeType an enum class.

third_party/WebKit/Source/core/style/ComputedStyle.h

Index: third_party/WebKit/Source/core/style/ComputedStyle.h
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.h b/third_party/WebKit/Source/core/style/ComputedStyle.h
index 9823d00a0dcc8a64af401490b4aef5d22413a90f..f8187ce3362495b65d9340a8a9fe4711b790de3a 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.h
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.h
@@ -1442,7 +1442,8 @@ class CORE_EXPORT ComputedStyle : public ComputedStyleBase<ComputedStyle>,
     SET_VAR(rare_non_inherited_data_, page_size_, s);
   }
   void SetPageSizeType(PageSizeType t) {
-    SET_VAR(rare_non_inherited_data_, page_size_type_, t);
+    SET_VAR(rare_non_inherited_data_, page_size_type_,
+            static_cast<unsigned>(t));
   }
 
   // Text decoration properties.
@@ -3052,7 +3053,8 @@ class CORE_EXPORT ComputedStyle : public ComputedStyleBase<ComputedStyle>,
 
   // Page size utility functions.
   void ResetPageSizeType() {
-    SET_VAR(rare_non_inherited_data_, page_size_type_, PAGE_SIZE_AUTO);
+    SET_VAR(rare_non_inherited_data_, page_size_type_,
+            static_cast<unsigned>(PageSizeType::kAuto));
   }
 
   // Outline utility functions.