idle-emulation-tests.js reformat

follow-up after CL 2317956

Bug: 1090802
Change-Id: I9ddbce522dc3860e429228510d89f7456fdc6f26
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2327670
Commit-Queue: Maksim Sadym <sadym@chromium.org>
Commit-Queue: Andrey Kosyakov <caseq@chromium.org>
Auto-Submit: Maksim Sadym <sadym@chromium.org>
Reviewed-by: Andrey Kosyakov <caseq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792868}

third_party/blink/web_tests/inspector-protocol/emulation/idle_detection/idle-emulation-tests.js

@@ -4,11 +4,6 @@
       var userState = null;
       var screenState = null;
 
-      var debug_output = "";
-      function debug_log(msg) {
-        debug_output += "\\\\n"+msg;
-      }
-
       function getState() {
         return "userState: " + userState + ", screenState: " + screenState;
       }
@@ -19,7 +14,6 @@
           idleDetector.addEventListener('change', (e) => {
             userState = idleDetector.userState;
             screenState = idleDetector.screenState;
-            debug_log("Idle change: "+userState+", "+screenState);
           });
 
           await idleDetector.start();
@@ -33,14 +27,10 @@
   `, 'Verifies that setIdleOverride overrides Idle state');
 
   async function evaluateAndWrite(cmd) {
-    let v = await evaluate(cmd);
+    let v = await session.evaluateAsync(cmd);
     testRunner.log(v);
   }
 
-  async function evaluate(cmd) {
-    return await session.evaluateAsync(cmd);
-  }
-
   await dp.Browser.grantPermissions({
     origin: location.origin,
     permissions: ['notifications'],
@@ -51,7 +41,7 @@
 
   // log initial state. It can be different based on the system.
   testRunner.log("remember initial state");
-  let initialState = await evaluate("getState()");
+  let initialState = await session.evaluateAsync("getState()");
 
   // Set overrides and verify state.
   testRunner.log("set isUserActive: false, isScreenUnlocked: false");
@@ -73,7 +63,7 @@
   // Clear overrides and verify state.
   testRunner.log("call clearIdleOverride");
   await dp.Emulation.clearIdleOverride();
-  let stateAfterClearingOverrides = await evaluate("getState()");
+  let stateAfterClearingOverrides = await session.evaluateAsync("getState()");
 
   if(stateAfterClearingOverrides == initialState) {
     testRunner.log("State after clearIdleOverride equals initial state");
@@ -81,6 +71,5 @@
     testRunner.log('[FAIL]: ' + stateAfterClearingOverrides + ' instead of ' + initialState);
   }
 
-
   testRunner.completeTest();
 })
\ No newline at end of file