[DevTools] Do not expose agents on Target

third_party/WebKit/Source/devtools/front_end/coverage/CoverageModel.js

Index: third_party/WebKit/Source/devtools/front_end/coverage/CoverageModel.js
diff --git a/third_party/WebKit/Source/devtools/front_end/coverage/CoverageModel.js b/third_party/WebKit/Source/devtools/front_end/coverage/CoverageModel.js
index 8f339c9245527c394648340d5ea394704e677e3e..30f601aefb2b6150e77a510666039cb45f281cde 100644
--- a/third_party/WebKit/Source/devtools/front_end/coverage/CoverageModel.js
+++ b/third_party/WebKit/Source/devtools/front_end/coverage/CoverageModel.js
@@ -16,12 +16,12 @@ Coverage.CoverageType = {
   JavaScript: (1 << 1),
 };
 
-Coverage.CoverageModel = class extends SDK.SDKModel {
+Coverage.CoverageModel = class {
   /**
    * @param {!SDK.Target} target
    */
   constructor(target) {
-    super(target);
+    this._target = target;

[caseq, 2017/04/29 02:12:53]

Is it still necessary?

     this._cpuProfilerModel = target.model(SDK.CPUProfilerModel);
     this._cssModel = target.model(SDK.CSSModel);
     this._debuggerModel = target.model(SDK.DebuggerModel);