webview: add permission-request event

docs/api/web-view-tag.md

@@ -167,6 +167,14 @@ A list of strings which specifies the blink features to be enabled separated by
 The full list of supported feature strings can be found in the
 [setFeatureEnabledFromString][blink-feature-string] function.
 
+### `disablewebnotification`
+
+```html
+<webview src="https://www.github.com/" disablewebnotification></webview>
+```
+
+If "on", the guest page will have web notifications disabled.
+
 ## Methods
 
 The `webview` tag has the following methods:
@@ -736,4 +744,22 @@ Emitted when DevTools is closed.
 
 Emitted when DevTools is focused / opened.
 
+### Event: 'permission-request'
+
+Returns:
+
+* `permission` String - The type of permission being requested. Enum of 'media', 'webNotification'.
+* `allow` Function - Allows the permission.
+* `deny` Function - Deny the permission. This is the default behaviour if `allow` is not called.
+
+Emitted when guest page requires special permission.
+
+```javascript
+// This will deny guest page access to the webkitGetUserMedia API.
+webview.addEventListener('permission-request', function(e) {
+  if (e.permission === 'media')
+    e.deny();
+});
+```
+
 [blink-feature-string]: https://code.google.com/p/chromium/codesearch#chromium/src/out/Debug/gen/blink/platform/RuntimeEnabledFeatures.cpp&sq=package:chromium&type=cs&l=527