DevTools: Add timestamp support in the console

Source/devtools/front_end/ConsoleViewMessage.js

Index: Source/devtools/front_end/ConsoleViewMessage.js
diff --git a/Source/devtools/front_end/ConsoleViewMessage.js b/Source/devtools/front_end/ConsoleViewMessage.js
index 18f54e27ffa3d8275ec9a5b94247573f2ec6f2e8..4b4aa2e7150185d091ed33a4e6f2fa2f3af56b9b 100644
--- a/Source/devtools/front_end/ConsoleViewMessage.js
+++ b/Source/devtools/front_end/ConsoleViewMessage.js
@@ -52,6 +52,8 @@ WebInspector.ConsoleViewMessage = function(target, consoleMessage, linkifier)
         "node":   this._formatParameterAsNode,
         "string": this._formatParameterAsString
     };
+
+    WebInspector.settings.consoleTimestampsEnabled.addChangeListener(this._consoleTimestampsSettingChanged, this);
 }
 
 WebInspector.ConsoleViewMessage.prototype = {
@@ -845,6 +847,29 @@ WebInspector.ConsoleViewMessage.prototype = {
         return regexObject.test(this._formattedMessageText()) || (!!this._anchorElement && regexObject.test(this._anchorElement.textContent));
     },
 
+    _updateTimestamp: function(show)
+    {
+        if (!this._element)
+            return;
+
+        if (show && !this.timestampElement) {
+            this.timestampElement = this._element.createChild("span", "console-timestamp");
+            this.timestampElement.textContent = (new Date(this._message.timestamp)).toConsoleTime();
+            var afterRepeatCountChild = this.repeatCountElement && this.repeatCountElement.nextSibling;
+            this._element.insertBefore(this.timestampElement, afterRepeatCountChild || this._element.firstChild);
+            return;
+        }
+
+        if (!show && this.timestampElement)
+            this.timestampElement.remove();
+    },
+
+    _consoleTimestampsSettingChanged: function(event)
+    {
+        var enabled = /** @type {boolean} */ (event.data);
+        this._updateTimestamp(enabled);
+    },
+
     /**
      * @return {!Element}
      */
@@ -885,6 +910,8 @@ WebInspector.ConsoleViewMessage.prototype = {
         if (this._repeatCount > 1)
             this._showRepeatCountElement();
 
+        this._updateTimestamp(WebInspector.settings.consoleTimestampsEnabled.get());
+
         return element;
     },
 
@@ -913,9 +940,10 @@ WebInspector.ConsoleViewMessage.prototype = {
         }
     },
 
-    incrementRepeatCount: function()
+    incrementRepeatCount: function(timestamp)
     {
         this._repeatCount++;
+        this._message.timestamp = timestamp
         this._showRepeatCountElement();
     },