[DevTools] Access cpu profiler only when JS capability is present.

third_party/WebKit/Source/devtools/front_end/profiler/CPUProfileView.js

Index: third_party/WebKit/Source/devtools/front_end/profiler/CPUProfileView.js
diff --git a/third_party/WebKit/Source/devtools/front_end/profiler/CPUProfileView.js b/third_party/WebKit/Source/devtools/front_end/profiler/CPUProfileView.js
index 41c7f04aaa0d149b3572ae6c6a6ccea5229fe191..2114d0a901dcd41c108736e022792ce86044b44f 100644
--- a/third_party/WebKit/Source/devtools/front_end/profiler/CPUProfileView.js
+++ b/third_party/WebKit/Source/devtools/front_end/profiler/CPUProfileView.js
@@ -189,16 +189,16 @@ Profiler.CPUProfileType = class extends Profiler.ProfileType {
   }
 
   startRecordingProfile() {
-    var target = UI.context.flavor(SDK.Target);
-    if (this.profileBeingRecorded() || !target)
+    var cpuProfilerModel = UI.context.flavor(SDK.CPUProfilerModel);
+    if (this.profileBeingRecorded() || !cpuProfilerModel)
       return;
-    var profile = new Profiler.CPUProfileHeader(target, this);
+    var profile = new Profiler.CPUProfileHeader(cpuProfilerModel.target(), this);
     this.setProfileBeingRecorded(profile);
     SDK.targetManager.suspendAllTargets();
     this.addProfile(profile);
     profile.updateStatus(Common.UIString('Recording\u2026'));
     this._recording = true;
-    target.cpuProfilerModel.startRecording();
+    cpuProfilerModel.startRecording();
   }
 
   stopRecordingProfile() {
@@ -231,7 +231,8 @@ Profiler.CPUProfileType = class extends Profiler.ProfileType {
 
     this.profileBeingRecorded()
         .target()

[alph, 2017/02/28 23:59:13]

nit: I'd rather write the synchronous part in a single line.

[dgozman, 2017/03/01 00:18:41]

That's what I did, but formatter thinks differently.

-        .cpuProfilerModel.stopRecording()
+        .model(SDK.CPUProfilerModel)
+        .stopRecording()
         .then(didStopProfiling.bind(this))
         .then(SDK.targetManager.resumeAllTargets.bind(SDK.targetManager))
         .then(fireEvent.bind(this));