[heap] Use size_t throughout MemoryAllocator

src/regexp/jsregexp.h

Index: src/regexp/jsregexp.h
diff --git a/src/regexp/jsregexp.h b/src/regexp/jsregexp.h
index 6e762b7657d9b4de15fbee388bee5cc2f9bff010..811888996652ccd7baaf1a239ce046b30d084b7a 100644
--- a/src/regexp/jsregexp.h
+++ b/src/regexp/jsregexp.h
@@ -200,7 +200,7 @@ class RegExpImpl {
   // is not tracked, however.  As a conservative approximation we track the
   // total regexp code compiled including code that has subsequently been freed
   // and the total executable memory at any point.
-  static const int kRegExpExecutableMemoryLimit = 16 * MB;
+  static const size_t kRegExpExecutableMemoryLimit = 16 * MB;
   static const int kRegExpCompiledLimit = 1 * MB;
   static const int kRegExpTooLargeToOptimize = 20 * KB;