Unified the structure of VirtualMemory implementations across platforms a bit.

src/platform-win32.cc

Index: src/platform-win32.cc
diff --git a/src/platform-win32.cc b/src/platform-win32.cc
index da2b741dc36cd9e1472070ed0b537da498d8eb82..f4097f708d26499d98e38e4b8164526b500628a3 100644
--- a/src/platform-win32.cc
+++ b/src/platform-win32.cc
@@ -1518,7 +1518,7 @@ VirtualMemory::VirtualMemory(size_t size, size_t alignment)
 
 VirtualMemory::~VirtualMemory() {
   if (IsReserved()) {
-    bool result = ReleaseRegion(address_, size_);
+    bool result = ReleaseRegion(address(), size());
     ASSERT(result);
     USE(result);
   }
@@ -1551,6 +1551,17 @@ bool VirtualMemory::Uncommit(void* address, size_t size) {
 }
 
 
+bool VirtualMemory::Guard(void* address) {
+  if (NULL == VirtualAlloc(address,
+                           OS::CommitPageSize(),
+                           MEM_COMMIT,
+                           PAGE_READONLY | PAGE_GUARD)) {
+    return false;
+  }
+  return true;
+}
+
+
 void* VirtualMemory::ReserveRegion(size_t size) {
   return RandomizedVirtualAlloc(size, MEM_RESERVE, PAGE_NOACCESS);
 }
@@ -1567,17 +1578,6 @@ bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) {
 }
 
 
-bool VirtualMemory::Guard(void* address) {
-  if (NULL == VirtualAlloc(address,
-                           OS::CommitPageSize(),
-                           MEM_COMMIT,
-                           PAGE_READONLY | PAGE_GUARD)) {
-    return false;
-  }
-  return true;
-}
-
-
 bool VirtualMemory::UncommitRegion(void* base, size_t size) {
   return VirtualFree(base, size, MEM_DECOMMIT) != 0;
 }