Revert "[DevTools] Make log agent optional."

third_party/WebKit/Source/devtools/front_end/sdk/ConsoleModel.js

Index: third_party/WebKit/Source/devtools/front_end/sdk/ConsoleModel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/sdk/ConsoleModel.js b/third_party/WebKit/Source/devtools/front_end/sdk/ConsoleModel.js
index 20d6df070b8ac8afa91d05459657a515ec22cf8a..a77974c551e79737e4dc2ece37723649b288618a 100644
--- a/third_party/WebKit/Source/devtools/front_end/sdk/ConsoleModel.js
+++ b/third_party/WebKit/Source/devtools/front_end/sdk/ConsoleModel.js
@@ -32,9 +32,8 @@
  * @constructor
  * @extends {WebInspector.SDKModel}
  * @param {!WebInspector.Target} target
- * @param {?Protocol.LogAgent} logAgent
  */
-WebInspector.ConsoleModel = function(target, logAgent)
+WebInspector.ConsoleModel = function(target)
 {
     WebInspector.SDKModel.call(this, WebInspector.ConsoleModel, target);
 
@@ -45,11 +44,9 @@ WebInspector.ConsoleModel = function(target, logAgent)
     this._warnings = 0;
     this._errors = 0;
     this._revokedErrors = 0;
-    this._logAgent = logAgent;
-    if (this._logAgent) {
-        target.registerLogDispatcher(new WebInspector.LogDispatcher(this));
-        this._logAgent.enable();
-    }
+    this._logAgent = target.logAgent();
+    target.registerLogDispatcher(new WebInspector.LogDispatcher(this));
+    this._logAgent.enable();
 }
 
 /** @enum {symbol} */
@@ -137,7 +134,7 @@ WebInspector.ConsoleModel.prototype = {
 
     requestClearMessages: function()
     {
-        this._logAgent && this._logAgent.clear();
+        this._logAgent.clear();
         this.clear();
     },