allow binding listeners to Debugger when not connected

app/src/lib/debugger/client/cri.js

@@ -105,12 +105,6 @@ class CriDebugger {
     return this.tabId_ !== null;
   }
 
-  throwIfNotConnected_() {
-    if (!this.isConnected()) {
-      throw new Error('Debugger is not connected.');
-    }
-  }
-
   connect(tabId) {
     if (this.tabId_ !== null) {
       return Promise.resolve();
@@ -142,7 +136,6 @@ class CriDebugger {
    * @param {function(...)} cb
    */
   on(eventName, cb) {
-    this.throwIfNotConnected_();
     this.client_.on(eventName, cb);
   }
 
@@ -154,7 +147,6 @@ class CriDebugger {
    * @param {function(...)} cb
    */
   once(eventName, cb) {
-    this.throwIfNotConnected_();
     this.client_.once(eventName, cb);
   }
 
@@ -165,7 +157,6 @@ class CriDebugger {
    * @param {function(...)} cb
    */
   off(eventName, cb) {
-    this.throwIfNotConnected_();
     this.client_.removeListener(eventName, cb);
   }
 
@@ -197,10 +188,8 @@ class CriDebugger {
    * @return {!Promise}
    */
   sendCommand(command, params, timeout) {
-    try {
-      this.throwIfNotConnected_();
-    } catch(e) {
-      return Promise.reject(e);
+    if (!this.isConnected()) {
+      return Promise.reject(new Error('Debugger is not connected.'));
     }
 
     return new Promise((resolve, reject) => {

app/src/lib/debugger/client/extension.js

@@ -118,12 +118,6 @@ class ExtensionDebugger extends EventEmitter {
     return this.tabId_ !== null;
   }
 
-  throwIfNotConnected_() {
-    if (!this.isConnected()) {
-      throw new Error('Debugger is not connected.');
-    }
-  }
-
   connect(tabId) {
     if (this.tabId_ !== null) {
       return Promise.resolve();
@@ -166,7 +160,6 @@ class ExtensionDebugger extends EventEmitter {
    * @param {function(...)} cb
    */
   on(eventName, cb) {
-    this.throwIfNotConnected_();
     super.on(eventName, cb);
   }
 
@@ -178,7 +171,6 @@ class ExtensionDebugger extends EventEmitter {
    * @param {function(...)} cb
    */
   once(eventName, cb) {
-    this.throwIfNotConnected_();
     super.once(eventName, cb);
   }
 
@@ -189,7 +181,6 @@ class ExtensionDebugger extends EventEmitter {
    * @param {function(...)} cb
    */
   off(eventName, cb) {
-    this.throwIfNotConnected_();
     super.removeListener(eventName, cb);
   }
 
@@ -221,10 +212,8 @@ class ExtensionDebugger extends EventEmitter {
    * @return {!Promise}
    */
   sendCommand(command, params, timeout) {
-    try {
-      this.throwIfNotConnected_();
-    } catch(e) {
-      return Promise.reject(e);
+    if (!this.isConnected()) {
+      return Promise.reject(new Error('Debugger is not connected.'));
     }
 
     return new Promise((resolve, reject) => {

app/src/lib/debugger/client/extension.test.js

@@ -51,11 +51,7 @@ describe('debugger', () => {
     describe('is event emitter', () => {
       let EVENT = 'some event', spy;
 
-      beforeEach(() => {
-        spy = sinon.spy();
-        return dbg.connect(tab.id);
-      });
-      afterEach(() => dbg.disconnect());
+      beforeEach(() => spy = sinon.spy());
 
       it('on', () => {
         dbg.on(EVENT, spy);

app/src/lib/debugger/client/fake.js

@@ -37,7 +37,7 @@ class FakeDebugger extends EventEmitter {
     super();
 
     this.tabId_ = null;
-    this.commandToResultMap_ = new Map();
+    this.commandResultMap_ = new Map();
   }
 
   getTabId() {
@@ -68,53 +68,33 @@ class FakeDebugger extends EventEmitter {
   }
 
   on(eventName, cb) {
-    if (this.tabId_ === null) {
-      throw new Error('connect() must be called before attempting to listen to events.');
-    }
-
     super.on(eventName, cb);
   }
 
   once(eventName, cb) {
-    if (this.tabId_ === null) {
-      throw new Error('connect() must be called before attempting to listen to events.');
-    }
-
     super.once(eventName, cb);
   }
 
   off(eventName, cb) {
-    if (this.tabId_ === null) {
-      throw new Error('connect() must be called before attempting to listen to events.');
-    }
-
     super.removeListener(eventName, cb);
   }
 
   onCommandSuccess(cb) {
-    if (this.tabId_ === null) {
-      throw new Error('connect() must be called before attempting to listen to events.');
-    }
-
-    super.on('commandSuccess', cb);
+    this.on('commandSuccess', cb);
   }
 
   offCommandSuccess(cb) {
-    if (this.tabId_ === null) {
-      throw new Error('connect() must be called before attempting to listen to events.');
-    }
-
-    super.removeListener('commandSuccess', cb);
+    this.off('commandSuccess', cb);
   }
 
   sendCommand(command, params, timeout) {
-    if (this.tabId_ === null) {
-      return Promise.reject(new Error('connect() must be called before attempting to send commands.'));
+    if (!this.isConnected()) {
+      return Promise.reject(new Error('Debugger is not connected.'));
     }
 
     this.emit('commandSuccess', command, {}, timeout);
 
-    return Promise.resolve(this.commandToResultMap_.get(command) || {});
+    return Promise.resolve(this.commandResultMap_.get(command) || {});
   }
 
   /**
@@ -124,7 +104,7 @@ class FakeDebugger extends EventEmitter {
    * @param {any} result
    */
   setCommandResult(command, result) {
-    this.commandToResultMap_.set(command, result);
+    this.commandResultMap_.set(command, result);
     return this;
   }
 }

app/src/lib/debugger/navigation_tracker.js

@@ -148,7 +148,7 @@ class NavigationTracker extends NavigationTrackerInterface {
         }
       })
       .catch(e => {
-        if (/connect\(\) must be called/i.test(e.message)) {
+        if (/not connected/i.test(e.message)) {
           // If the debugger is not connected, don't wait for pending navigations
           // to complete, since we won't see any more events from it until we reconnect.
           isPending = false;

app/src/lib/debugger/navigation_tracker.test.js

@@ -104,9 +104,8 @@ describe('debugger', () => {
       });
 
       it('resolves false if debugger is not connected', () => {
-        dbg.disconnect();
-
-        return tracker.isPendingNavigation()
+        return dbg.disconnect()
+          .then(() => tracker.isPendingNavigation())
           .then(pending => expect(pending).to.be.false);
       });