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

chrome/common/metrics_helpers.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/metrics_helpers.h"
 
 #if defined(USE_SYSTEM_LIBBZ2)
 #include <bzlib.h>
 #else
 #include "third_party/bzip2/bzlib.h"
@@ skipping 34 matching lines @@
 
 }  // namespace
 
 class MetricsLogBase::XmlWrapper {
  public:
   XmlWrapper()
       : doc_(NULL),
         buffer_(NULL),
         writer_(NULL) {
     buffer_ = xmlBufferCreate();
-    DCHECK(buffer_);
+    CHECK(buffer_);
 
     #if defined(OS_CHROMEOS)
       writer_ = xmlNewTextWriterDoc(&doc_, /* compression */ 0);
     #else
       writer_ = xmlNewTextWriterMemory(buffer_, /* compression */ 0);
     #endif  // OS_CHROMEOS
     DCHECK(writer_);
 
     int result = xmlTextWriterSetIndent(writer_, 2);
     DCHECK_EQ(0, result);
@@ skipping 78 matching lines @@
   UMA_HISTOGRAM_TIMES("UMA.XMLNodeDumpTime", dump_timer.Elapsed());
 
   PerfTimer free_timer;
   xml_wrapper_->FreeDocWriter();
   UMA_HISTOGRAM_TIMES("UMA.XMLWriterDestructionTime", free_timer.Elapsed());
 #endif  // OS_CHROMEOS
 }
 
 int MetricsLogBase::GetEncodedLogSize() {
   DCHECK(locked_);
+  CHECK(xml_wrapper_);
+  CHECK(xml_wrapper_->buffer());
   return xml_wrapper_->buffer()->use;
 }
 
 bool MetricsLogBase::GetEncodedLog(char* buffer, int buffer_size) {
   DCHECK(locked_);
   if (buffer_size < GetEncodedLogSize())
     return false;
 
   memcpy(buffer, xml_wrapper_->buffer()->content, GetEncodedLogSize());
   return true;
@@ skipping 406 matching lines @@
     snapshot.Subtract(*already_logged);
   }
 
   // Snapshot now contains only a delta to what we've already_logged.
   if (snapshot.redundant_count() > 0) {
     TransmitHistogramDelta(histogram, snapshot);
     // Add new data into our running total.
     already_logged->Add(snapshot);
   }
 }