Fixes a memory leak when running webrtc-internals for a long time, by using a circular buffer of si…

content/browser/resources/media/timeline_graph_view.js

Index: content/browser/resources/media/timeline_graph_view.js
diff --git a/content/browser/resources/media/timeline_graph_view.js b/content/browser/resources/media/timeline_graph_view.js
index bb3557d995958ad08faa7d410ca2b581593b9164..89b557e1710095935eae8344d01f809035c8b75f 100644
--- a/content/browser/resources/media/timeline_graph_view.js
+++ b/content/browser/resources/media/timeline_graph_view.js
@@ -214,41 +214,8 @@ var TimelineGraphView = (function() {
      * time range.
      */
     drawTimeLabels: function(context, width, height, textHeight, startTime) {
-      // Text for a time string to use in determining how far apart
-      // to place text labels.
-      var sampleText = (new Date(startTime)).toLocaleTimeString();
-
-      // The desired spacing for text labels.
-      var targetSpacing = context.measureText(sampleText).width +
-                              LABEL_LABEL_HORIZONTAL_SPACING;
-
-      // The allowed time step values between adjacent labels.  Anything much
-      // over a couple minutes isn't terribly realistic, given how much memory
-      // we use, and how slow a lot of the net-internals code is.
-      var timeStepValues = [
-        1000,  // 1 second
-        1000 * 5,
-        1000 * 30,
-        1000 * 60,  // 1 minute
-        1000 * 60 * 5,
-        1000 * 60 * 30,
-        1000 * 60 * 60,  // 1 hour
-        1000 * 60 * 60 * 5
-      ];
-
-      // Find smallest time step value that gives us at least |targetSpacing|,
-      // if any.
-      var timeStep = null;
-      for (var i = 0; i < timeStepValues.length; ++i) {
-        if (timeStepValues[i] / DEFAULT_SCALE >= targetSpacing) {
-          timeStep = timeStepValues[i];
-          break;
-        }
-      }
-
-      // If no such value, give up.
-      if (!timeStep)
-        return;
+      // Draw the labels 1 minute apart.
+      var timeStep = 1000 * 60;
 
       // Find the time for the first label.  This time is a perfect multiple of
       // timeStep because of how UTC times work.