More DCHECK() updates. A mixture of _EQ and _GE.

base/shared_memory_win.cc

Index: base/shared_memory_win.cc
diff --git a/base/shared_memory_win.cc b/base/shared_memory_win.cc
index 15c61ddf00def5295ffb857cd1082d82c27c4551..526132c28517f90591c3d740372dd44b5e50166d 100644
--- a/base/shared_memory_win.cc
+++ b/base/shared_memory_win.cc
@@ -80,7 +80,7 @@ bool SharedMemory::CreateAnonymous(uint32 size) {
 
 bool SharedMemory::CreateNamed(const std::string& name,
                                bool open_existing, uint32 size) {
-  DCHECK(mapped_file_ == NULL);
+  DCHECK(!mapped_file_);
   if (size == 0)
     return false;
 
@@ -119,7 +119,7 @@ bool SharedMemory::Delete(const std::string& name) {
 }
 
 bool SharedMemory::Open(const std::string& name, bool read_only) {
-  DCHECK(mapped_file_ == NULL);
+  DCHECK(!mapped_file_);
 
   name_ = ASCIIToWide(name);
   read_only_ = read_only;