[inspector] extend protocol for code coverage.

test/inspector/runtime/coverage.js

Index: test/inspector/runtime/coverage.js
diff --git a/test/inspector/runtime/coverage.js b/test/inspector/runtime/coverage.js
new file mode 100644
index 0000000000000000000000000000000000000000..5f9200de7ea66d66a42193c2dd5c4d03fa439fe3
--- /dev/null
+++ b/test/inspector/runtime/coverage.js
@@ -0,0 +1,32 @@
+// 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.
+
+var source =
+`
+function fib(x) {
+  if (x < 2) return 1;
+  return fib(x-1) + fib(x-2);
+}
+fib(5);
+`;
+
+var url = "fib.js"
+
+print("Test collecting code coverage data with Runtime.collectCoverage.");
+
+InspectorTest.runTestSuite([
+  function testCoverage(next)
+  {
+    Protocol.Runtime.enable()
+      .then(() => Protocol.Runtime.startPreciseCoverage())
+      .then(() => Protocol.Runtime.compileScript({ expression: source, sourceURL: url, persistScript: true }))
+      .then((result) => Protocol.Runtime.runScript({ scriptId: result.result.scriptId }))
+      .then((result) => InspectorTest.logMessage(result))
+      .then(() => Protocol.Runtime.collectCoverage())
+      .then((result) => InspectorTest.logMessage(result))
+      .then(() => Protocol.Runtime.stopPreciseCoverage())
+      .then(() => Protocol.Runtime.disable())
+      .then(() => next());
+  }
+]);