Add histogram metrics for video playback freezes

Bug: 234833109
Test: atest VideoRenderQualityTracker_test
Change-Id: I5e3a8b02336bbcbe639aad37f0914ba0f98d8d44
diff --git a/media/libmediametrics/MediaMetrics.cpp b/media/libmediametrics/MediaMetrics.cpp
index a3c2f1a..2240223 100644
--- a/media/libmediametrics/MediaMetrics.cpp
+++ b/media/libmediametrics/MediaMetrics.cpp
@@ -86,6 +86,11 @@
     if (item != NULL) item->setRate(attr, count, duration);
 }
 
+void mediametrics_setString(mediametrics_handle_t handle, attr_t attr,
+                                 const std::string &string) {
+    mediametrics_setCString(handle, attr, string.c_str());
+}
+
 void mediametrics_setCString(mediametrics_handle_t handle, attr_t attr,
                                  const char *value) {
     Item *item = (Item *) handle;
@@ -152,6 +157,14 @@
     return item->getRate(attr, count, duration, rate);
 }
 
+bool mediametrics_getString(mediametrics_handle_t handle, attr_t attr,
+                                 std::string *string) {
+    Item *item = (Item *) handle;
+    if (item == NULL) return false;
+
+    return item->getString(attr, string);
+}
+
 // NB: caller owns the string that comes back, is responsible for freeing it
 bool mediametrics_getCString(mediametrics_handle_t handle, attr_t attr,
                                  char **value) {