Change some integer types to make the x64 Win32 platform happier.

src/objects-inl.h

Index: src/objects-inl.h
===================================================================
--- src/objects-inl.h	(revision 2742)
+++ src/objects-inl.h	(working copy)
@@ -814,15 +814,13 @@
 
 Failure* Failure::Construct(Type type, int value) {
   int info = (value << kFailureTypeTagSize) | type;
-  // TODO(X64): Stop using Smi validation for non-smi checks, even if they
-  // happen to be identical at the moment.
-  ASSERT(Smi::IsValid(info));  // Same validation check as in Smi
+  ASSERT(((info << kFailureTagSize) >> kFailureTagSize) == info);
   return reinterpret_cast<Failure*>(
       (static_cast<intptr_t>(info) << kFailureTagSize) | kFailureTag);
 }
 
 
-bool Smi::IsValid(int value) {
+bool Smi::IsValid(intptr_t value) {
 #ifdef DEBUG
   bool in_range = (value >= kMinValue) && (value <= kMaxValue);
 #endif
@@ -937,12 +935,13 @@
 
 
 Address MapWord::DecodeMapAddress(MapSpace* map_space) {
-  int map_page_index = (value_ & kMapPageIndexMask) >> kMapPageIndexShift;
+  int map_page_index =
+      static_cast<int>((value_ & kMapPageIndexMask) >> kMapPageIndexShift);
   ASSERT_MAP_PAGE_INDEX(map_page_index);
 
-  int map_page_offset =
+  int map_page_offset = static_cast<int>(
       ((value_ & kMapPageOffsetMask) >> kMapPageOffsetShift)
-      << kObjectAlignmentBits;
+      << kObjectAlignmentBits);
 
   return (map_space->PageAddress(map_page_index) + map_page_offset);
 }