Added CHECK for buffer_ and xml_wrapper_ to be not NULL ...

chrome/common/metrics_helpers.cc

Index: chrome/common/metrics_helpers.cc
===================================================================
--- chrome/common/metrics_helpers.cc	(revision 71223)
+++ chrome/common/metrics_helpers.cc	(working copy)
@@ -52,7 +52,7 @@
         buffer_(NULL),
         writer_(NULL) {
     buffer_ = xmlBufferCreate();
-    DCHECK(buffer_);
+    CHECK(buffer_);
 
     #if defined(OS_CHROMEOS)
       writer_ = xmlNewTextWriterDoc(&doc_, /* compression */ 0);
@@ -151,6 +151,8 @@
 
 int MetricsLogBase::GetEncodedLogSize() {
   DCHECK(locked_);
+  CHECK(xml_wrapper_);
+  CHECK(xml_wrapper_->buffer());
   return xml_wrapper_->buffer()->use;
 }