Add AudioDirectiveHandler timed tests.

components/copresence/handlers/audio/audio_directive_list.cc

Index: components/copresence/handlers/audio/audio_directive_list.cc
diff --git a/components/copresence/handlers/audio/audio_directive_list.cc b/components/copresence/handlers/audio/audio_directive_list.cc
index 8b9b76ec21d1945b9955ea17bba27e41e8b892c1..2060ef51048316ebcf4fa41a773c87b88096c702 100644
--- a/components/copresence/handlers/audio/audio_directive_list.cc
+++ b/components/copresence/handlers/audio/audio_directive_list.cc
@@ -8,8 +8,8 @@
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/default_tick_clock.h"
-#include "base/time/tick_clock.h"
 #include "base/time/time.h"
+#include "components/copresence/handlers/audio/tick_clock_ref_counted.h"
 
 namespace copresence {
 
@@ -23,7 +23,9 @@ AudioDirective::AudioDirective(const std::string& op_id,
     : op_id(op_id), end_time(end_time) {
 }
 
-AudioDirectiveList::AudioDirectiveList() : clock_(new base::DefaultTickClock) {
+AudioDirectiveList::AudioDirectiveList()
+    : clock_(new TickClockRefCounted(
+          make_scoped_ptr(new base::DefaultTickClock))) {
 }
 
 AudioDirectiveList::~AudioDirectiveList() {
@@ -75,6 +77,13 @@ scoped_ptr<AudioDirective> AudioDirectiveList::GetActiveDirective() {
   return make_scoped_ptr(new AudioDirective(active_directives_.front()));
 }
 
+void AudioDirectiveList::set_clock_for_testing(
+    const scoped_refptr<TickClockRefCounted>& clock) {
+  clock_ = clock;
+}
+
+// Private methods.
+
 std::vector<AudioDirective>::iterator AudioDirectiveList::FindDirectiveByOpId(
     const std::string& op_id) {
   for (std::vector<AudioDirective>::iterator it = active_directives_.begin();