Revert of [DevTools] Remove edited scripts from debugger agent, move knowledge to frontend.

Source/devtools/front_end/sdk/DebuggerModel.js

Index: Source/devtools/front_end/sdk/DebuggerModel.js
diff --git a/Source/devtools/front_end/sdk/DebuggerModel.js b/Source/devtools/front_end/sdk/DebuggerModel.js
index bb2b0325e471e0da7d6611053265db7ed6dad13f..9e18b1813515fff702b90322aabb23567c536800 100644
--- a/Source/devtools/front_end/sdk/DebuggerModel.js
+++ b/Source/devtools/front_end/sdk/DebuggerModel.js
@@ -125,21 +125,12 @@
     {
         if (this._debuggerEnabled)
             return;
-        this._agent.enable(this._wasEnabled.bind(this));
+        this._agent.enable();
+        this._debuggerEnabled = true;
         if (this._hasStaleState) {
             this._globalObjectCleared();
             this._hasStaleState = false;
         }
-    },
-
-    /**
-     * @param {?Protocol.Error} error
-     */
-    _wasEnabled: function(error)
-    {
-        if (error)
-            console.error(error);
-        this._debuggerEnabled = true;
         this._pauseOnExceptionStateChanged();
         this.asyncStackTracesStateChanged();
         this.dispatchEventToListeners(WebInspector.DebuggerModel.Events.DebuggerWasEnabled);