DevTools: Remove unused variables. Disallow unused variables with eslint

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

Index: third_party/WebKit/Source/devtools/front_end/sdk/DebuggerModel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/sdk/DebuggerModel.js b/third_party/WebKit/Source/devtools/front_end/sdk/DebuggerModel.js
index 7312c980c7ab6079828771caea67357f30162114..46f8339f1727bf3c89858cc3b82fcd48c67ab986 100644
--- a/third_party/WebKit/Source/devtools/front_end/sdk/DebuggerModel.js
+++ b/third_party/WebKit/Source/devtools/front_end/sdk/DebuggerModel.js
@@ -216,7 +216,6 @@ SDK.DebuggerModel = class extends SDK.SDKModel {
     }
     columnNumber = Math.max(columnNumber, minColumnNumber);
 
-    var target = this.target();
     /**
      * @param {?Protocol.Error} error
      * @param {!Protocol.Debugger.BreakpointId} breakpointId
@@ -240,8 +239,6 @@ SDK.DebuggerModel = class extends SDK.SDKModel {
    * @param {function(?Protocol.Debugger.BreakpointId, !Array.<!SDK.DebuggerModel.Location>)=} callback
    */
   setBreakpointBySourceId(rawLocation, condition, callback) {
-    var target = this.target();
-
     /**
      * @this {SDK.DebuggerModel}
      * @param {?Protocol.Error} error