fix PDFJS loading PDFs in new tabs

fix #8364

also adds LOAD_URL_REQUESTED message handler, which is needed for brave/pdf.js#2

test plan:
1. go to https://letsencrypt.org/repository/
2. right click on any of the links to open in a new tab. it should work.
3. right click on any of the links to open in a new private tab. it should work.

app/browser/tabs.js

@@ -5,7 +5,7 @@ const tabState = require('../common/state/tabState')
 const {app, BrowserWindow, extensions, session} = require('electron')
 const {makeImmutable} = require('../common/state/immutableUtil')
 const {getTargetAboutUrl, isSourceAboutUrl, newFrameUrl} = require('../../js/lib/appUrlUtil')
-const {isURL, getUrlFromInput} = require('../../js/lib/urlutil')
+const {isURL, getUrlFromInput, toPDFJSLocation} = require('../../js/lib/urlutil')
 const {isSessionPartition} = require('../../js/state/frameStateUtil')
 const {getOrigin} = require('../../js/state/siteUtil')
 const {getSetting} = require('../../js/settings')
@@ -29,6 +29,9 @@ const normalizeUrl = function (url) {
   if (isURL(url)) {
     url = getUrlFromInput(url)
   }
+  if (getSetting(settings.PDFJS_ENABLED)) {
+    url = toPDFJSLocation(url)
+  }
   return url
 }
 

app/extensions.js

@@ -3,6 +3,7 @@ const contextMenus = require('./browser/extensions/contextMenus')
 const extensionActions = require('./common/actions/extensionActions')
 const config = require('../js/constants/config')
 const appConfig = require('../js/constants/appConfig')
+const messages = require('../js/constants/messages')
 const {fileUrl} = require('../js/lib/appUrlUtil')
 const {getExtensionsPath, getBraveExtUrl, getBraveExtIndexHTML} = require('../js/lib/appUrlUtil')
 const {getSetting} = require('../js/settings')
@@ -16,6 +17,7 @@ const fs = require('fs')
 const path = require('path')
 const l10n = require('../js/l10n')
 const {bravifyText} = require('./renderer/lib/extensionsUtil')
+const ipcMain = require('electron').ipcMain
 
 // Takes Content Security Policy flags, for example { 'default-src': '*' }
 // Returns a CSP string, for example 'default-src: *;'
@@ -340,6 +342,10 @@ module.exports.init = () => {
     }
   })
 
+  ipcMain.on(messages.LOAD_URL_REQUESTED, (e, tabId, url) => {
+    appActions.loadURLRequested(tabId, url)
+  })
+
   process.on('reload-sync-extension', () => {
     console.log('reloading sync')
     disableExtension(config.syncExtensionId)

js/constants/messages.js

@@ -149,6 +149,8 @@ const messages = {
   SAVE_INIT_DATA: _,
   RELOAD_SYNC_EXTENSION: _,
   RESET_SYNC: _,
+  // PDFJS
+  LOAD_URL_REQUESTED: _,
   // Torrent
   TORRENT_MESSAGE: _
 }

js/lib/urlutil.js

@@ -314,6 +314,19 @@ const UrlUtil = {
     return url
   },
 
+  /**
+   * Converts a potential PDF URL to the PDFJS URL.
+   * XXX: This only looks at the URL file extension, not MIME types.
+   * @param {string} url
+   * @return {string}
+   */
+  toPDFJSLocation: function (url) {
+    if (url && UrlUtil.isHttpOrHttps(url) && UrlUtil.isFileType(url, 'pdf')) {
+      return `chrome-extension://${pdfjsExtensionId}/${url}`
+    }
+    return url
+  },
+
   /**
    * Gets location to display in the urlbar
    * @param {string} url

test/unit/lib/urlutilTest.js

@@ -189,6 +189,22 @@ describe('urlutil', function () {
     })
   })
 
+  describe('toPDFJSLocation', function () {
+    const baseUrl = 'chrome-extension://jdbefljfgobbmcidnmpjamcbhnbphjnb/'
+    it('pdf', function () {
+      assert.equal(UrlUtil.toPDFJSLocation('http://abc.com/test.pdf'), baseUrl + 'http://abc.com/test.pdf')
+    })
+    it('non-pdf', function () {
+      assert.equal(UrlUtil.toPDFJSLocation('http://abc.com/test.pdf.txt'), 'http://abc.com/test.pdf.txt')
+    })
+    it('file url', function () {
+      assert.equal(UrlUtil.toPDFJSLocation('file://abc.com/test.pdf.txt'), 'file://abc.com/test.pdf.txt')
+    })
+    it('empty', function () {
+      assert.equal(UrlUtil.toPDFJSLocation(''), '')
+    })
+  })
+
   describe('getHostname', function () {
     it('returns undefined if the URL is invalid', function () {
       assert.equal(UrlUtil.getHostname(null), undefined)