Re-enable several MSVC warnings

core/fxcrt/fx_basic_maps.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "core/fxcrt/plex.h"
 #include "core/include/fxcrt/fx_basic.h"
 
 CFX_MapPtrToPtr::CFX_MapPtrToPtr(int nBlockSize)
@@ skipping 21 matching lines @@
   return ((FX_DWORD)(uintptr_t)key) >> 4;
 }
 void CFX_MapPtrToPtr::GetNextAssoc(FX_POSITION& rNextPosition,
                                    void*& rKey,
                                    void*& rValue) const {
   ASSERT(m_pHashTable);
   CAssoc* pAssocRet = (CAssoc*)rNextPosition;
   ASSERT(pAssocRet);
   if (pAssocRet == (CAssoc*)-1) {
     for (FX_DWORD nBucket = 0; nBucket < m_nHashTableSize; nBucket++) {
-      if ((pAssocRet = m_pHashTable[nBucket]))
+      pAssocRet = m_pHashTable[nBucket];
+      if (pAssocRet)
         break;
     }
     ASSERT(pAssocRet);
   }
-  CAssoc* pAssocNext;
-  if ((pAssocNext = pAssocRet->pNext) == NULL) {
+  CAssoc* pAssocNext = pAssocRet->pNext;
+  if (!pAssocNext) {

[Tom Sepez, 2016/03/17 16:40:05]

Do we still need this if given the check at 51?

[Wei Li, 2016/03/18 17:42:39]

Done.

     for (FX_DWORD nBucket = (HashKey(pAssocRet->key) % m_nHashTableSize) + 1;

[Tom Sepez, 2016/03/17 16:40:05]

nit: [super nit] Maybe this reads cleaner as 
CAssoc* pAssocNext = pAssocRet->pNext;
FX_DWORD nBucket = (HashKey(pAssocRet->key) % m_nHashTableSize) + 1;
while (!pAssocNext && nBucket < m_nHashTableSize)
  pAssocNext = m_pHashTable[nBucket++];

but double-check my logic.  

[Wei Li, 2016/03/18 17:42:39]

I agree with you on the readability for the loop. On the other hand, the nBucket
can be confined within the loop. So how about leave it for now?

-         nBucket < m_nHashTableSize; nBucket++) {
-      if ((pAssocNext = m_pHashTable[nBucket])) {
-        break;
-      }
+         nBucket < m_nHashTableSize && !pAssocNext; nBucket++) {
+      pAssocNext = m_pHashTable[nBucket];
     }
   }
   rNextPosition = (FX_POSITION)pAssocNext;
   rKey = pAssocRet->key;
   rValue = pAssocRet->value;
 }
 FX_BOOL CFX_MapPtrToPtr::Lookup(void* key, void*& rValue) const {
   FX_DWORD nHash;
   CAssoc* pAssoc = GetAssocAt(key, nHash);
   if (!pAssoc) {
@@ skipping 86 matching lines @@
 }
 void CFX_MapPtrToPtr::FreeAssoc(CFX_MapPtrToPtr::CAssoc* pAssoc) {
   pAssoc->pNext = m_pFreeList;
   m_pFreeList = pAssoc;
   m_nCount--;
   ASSERT(m_nCount >= 0);
   if (m_nCount == 0) {
     RemoveAll();
   }
 }