Disk cache: Generate total-load-time histograms from the

disk cache experiment.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/155380

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@20452 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 13 insertions, 4 deletions

diff --git a/base/field_trial.cc b/base/field_trial.cc
index 2b354d7..0bf39e2 100644
--- a/base/field_trial.cc
+++ b/base/field_trial.cc
@@ -67,9 +67,12 @@ std::string FieldTrial::MakeName(const std::string& name_prefix,
 // static
 FieldTrialList* FieldTrialList::global_ = NULL;
 
-FieldTrialList::FieldTrialList()
-  : application_start_time_(Time::Now()) {
+// static
+bool FieldTrialList::register_without_global_ = false;
+
+FieldTrialList::FieldTrialList() : application_start_time_(Time::Now()) {
   DCHECK(!global_);
+  DCHECK(!register_without_global_);
   global_ = this;
 }
 
@@ -86,9 +89,10 @@ FieldTrialList::~FieldTrialList() {
 
 // static
 void FieldTrialList::Register(FieldTrial* trial) {
-  DCHECK(global_);
-  if (!global_)
+  if (!global_) {
+    register_without_global_ = true;
     return;
+  }
   AutoLock auto_lock(global_->lock_);
   DCHECK(!global_->PreLockedFind(trial->name()));
   trial->AddRef();
diff --git a/base/field_trial.h b/base/field_trial.h
index fba0b01..a26bde8f 100644
--- a/base/field_trial.h
+++ b/base/field_trial.h
@@ -210,6 +210,11 @@ class FieldTrialList {
 
   static FieldTrialList* global_;  // The singleton of this class.
 
+  // This will tell us if there is an attempt to register a field trial without
+  // creating the FieldTrialList. This is not an error, unless a FieldTrialList
+  // is created after that.
+  static bool register_without_global_;
+
   // A helper value made availabel to users, that shows when the FieldTrialList
   // was initialized.  Note that this is a singleton instance, and hence is a
   // good approximation to the start of the process.