Remove base's implicit_cast.

ui/base/page_transition_types.cc

Index: ui/base/page_transition_types.cc
diff --git a/ui/base/page_transition_types.cc b/ui/base/page_transition_types.cc
index 0bd86f613e3a2698145d01225183cd4c6f7b8ec0..62c4e5aaba2777238d20ac1491844b2c4bb6eb6c 100644
--- a/ui/base/page_transition_types.cc
+++ b/ui/base/page_transition_types.cc
@@ -11,10 +11,9 @@ namespace ui {
 bool PageTransitionCoreTypeIs(PageTransition lhs,
                               PageTransition rhs) {
   // Expect the rhs to be a compile time constant without qualifiers.
-  DCHECK(PageTransitionGetQualifier(rhs) == 0 &&
-      PageTransitionIsValidType(rhs));
-  return implicit_cast<int>(PageTransitionStripQualifier(lhs)) ==
-      implicit_cast<int>(PageTransitionStripQualifier(rhs));
+  DCHECK_EQ(PageTransitionGetQualifier(rhs), 0);
+  DCHECK(PageTransitionIsValidType(rhs));
+  return PageTransitionStripQualifier(lhs) == PageTransitionStripQualifier(rhs);
 }
 
 PageTransition PageTransitionStripQualifier(PageTransition type) {