Sakurai/pdf.js
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Feature detection after downgrading the browser.

Browse Source 
If a user downgrades from Chromium 35+ to 34, then the PDF Viewer
extension will not work any more because the extension assumes
that certain features were available based on the cached feature
detection results.

To resolve this problem, all feature detection scripts run again
if the browser was downgraded.
This commit is contained in:
Rob Wu 2014-07-25 22:44:03 +02:00
parent 1e21bac9d3
commit 87dacba9a6
1 changed files with 9 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
extensions/chromium/feature-detect.js
View File

@ -33,13 +33,20 @@ chrome.storage.local.get(Features, function(features) {
// Browser not upgraded, so the features did probably not change.
return;
}
// In case of a downgrade, the features must be tested again.
var lastVersion = /Chrome\/\d+\.0\.(\d+)/.exec(features.featureDetectLastUA);
lastVersion = lastVersion ? parseInt(lastVersion[1], 10) : 0;
var newVersion = /Chrome\/\d+\.0\.(\d+)/.exec(navigator.userAgent);
var isDowngrade = newVersion && parseInt(newVersion[1], 10) < lastVersion;
var inconclusiveTestCount = 0;
if (!features.extensionSupportsFTP) {
if (isDowngrade || !features.extensionSupportsFTP) {
features.extensionSupportsFTP = featureTestFTP();
}
if (!features.webRequestRedirectUrl) {
if (isDowngrade || !features.webRequestRedirectUrl) {
++inconclusiveTestCount;
// Relatively expensive (and asynchronous) test:
featureTestRedirectOnHeadersReceived(function(result) {