Record the PDF and top level URL when the PDF plugin crashes.

chrome/browser/resources/pdf/browser_api.js

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 'use strict';
 
 /**
  * Returns a promise that will resolve to the default zoom factor.
  * @param {!Object} streamInfo The stream object pointing to the data contained
  *     in the PDF.
@@ skipping 134 matching lines @@
 
 /**
  * Creates a BrowserApi for an extension running as a mime handler.
  * @return {Promise<BrowserApi>} A promise to a BrowserApi instance constructed
  *     using the mimeHandlerPrivate API.
  */
 function createBrowserApiForMimeHandlerView() {
   return new Promise(function(resolve, reject) {
     chrome.mimeHandlerPrivate.getStreamInfo(resolve);
   }).then(function(streamInfo) {
-    let manageZoom = !streamInfo.embedded && streamInfo.tabId != -1;
     return new Promise(function(resolve, reject) {

[Sam McNally, 2016/09/07 07:53:02]

I'd prefer doing both API calls in parallel. Something like
let promises = [];
if (streamInfo.tabId != -1) {
  promises.push(new Promise(resolve => {
    chrome.tabs.get(..., resolve);
  }).then(tab => {
    if (tab)
      streamInfo.tabUrl = tab.url;
  });
  if (!streamInfo.embedded) {
    promises.push(new Promise(resolve => {
      chrome.tabs.setZoomSettings(..., resolve);
    }));
  }
}
return Promise.all(promises);

[Lei Zhang, 2016/09/08 01:10:31]

Done. Hope I got it right. A JS presubmit check does not like => syntax.

-      if (!manageZoom) {
-        resolve();
+      if (streamInfo.tabId == -1) {
+        resolve(false);

[raymes, 2016/09/07 06:10:14]

nit: Maybe just resolve() or resolve(null) since the expected type is an object?

[Lei Zhang, 2016/09/08 01:10:31]

Done.

         return;
       }
-      chrome.tabs.setZoomSettings(
-          streamInfo.tabId, {mode: 'manual', scope: 'per-tab'}, resolve);
-    }).then(function() { return BrowserApi.create(streamInfo, manageZoom); });
+      chrome.tabs.get(streamInfo.tabId, resolve);
+    }).then(function(tab) {
+      let manageZoom = !streamInfo.embedded && streamInfo.tabId != -1;
+      return new Promise(function(resolve, reject) {
+        if (tab)
+          streamInfo.tabUrl = tab.url;
+        if (!manageZoom) {
+          resolve();
+          return;
+        }
+        chrome.tabs.setZoomSettings(
+            streamInfo.tabId, {mode: 'manual', scope: 'per-tab'}, resolve);
+      }).then(function() { return BrowserApi.create(streamInfo, manageZoom); });

[raymes, 2016/09/07 06:10:14]

This looks good to me, but I'm also not great with promises. +sammc to have an
additional look

[Lei Zhang, 2016/09/08 01:10:31]

Acknowledged.

+    });
   });
 }
 
 /**
  * Creates a BrowserApi instance for an extension not running as a mime handler.
  * @return {Promise<BrowserApi>} A promise to a BrowserApi instance constructed
  *     from the URL.
  */
 function createBrowserApiForStandaloneExtension() {
   let url = window.location.search.substring(1);
   let streamInfo = {
     streamUrl: url,
     originalUrl: url,
     responseHeaders: {},
     embedded: window.parent != window,
     tabId: -1,
   };
   return new Promise(function(resolve, reject) {
     if (!chrome.tabs) {
       resolve();
       return;
     }
     chrome.tabs.getCurrent(function(tab) {
       streamInfo.tabId = tab.id;
+      streamInfo.tabUrl = tab.url;
       resolve();
     });
   }).then(function() { return BrowserApi.create(streamInfo, false); });
 }
 
 /**
  * Returns a promise that will resolve to a BrowserApi instance.
  * @return {Promise<BrowserApi>} A promise to a BrowserApi instance for the
  *     current environment.
  */
 function createBrowserApi() {
   if (window.location.search)
     return createBrowserApiForStandaloneExtension();
 
   return createBrowserApiForMimeHandlerView();
 }