[tests] Cleanup tests that use assertOptimized()/assertUnoptimized().

test/inspector/debugger/pause-on-oom.js

 // Copyright 2017 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
-// Flags: --max_old_space_size=4
+
+// Flags: --max-old-space-size=4
 
 print('Check pause on OOM');
 
 InspectorTest.addScript(`
 var arr = [];
 var stop = false;
 function generateGarbage() {
   while(!stop) {
     arr.push(42);
   }
 }
 //# sourceURL=test.js`, 10, 26);
 
 Protocol.Debugger.onPaused((message) => {
   InspectorTest.log(`reason: ${message.params.reason}`);
   Protocol.Debugger.evaluateOnCallFrame({
     callFrameId: message.params.callFrames[0].callFrameId,
     expression: 'arr = []; stop = true;'
   }).then(() => Protocol.Debugger.resume());
 });
 Protocol.Debugger.enable();
 Protocol.Runtime.evaluate({ expression: 'generateGarbage()' })
   .then(InspectorTest.completeTest);