Support the removal of only session cookies or persistent cookies

extensions/common/api/web_view_internal.json

Index: extensions/common/api/web_view_internal.json
diff --git a/extensions/common/api/web_view_internal.json b/extensions/common/api/web_view_internal.json
index 94a6eb9820bf547338b745d39d338f75de8c6be6..d15a9a277f8cfc2cfee8585f3dd0531f7055da55 100644
--- a/extensions/common/api/web_view_internal.json
+++ b/extensions/common/api/web_view_internal.json
@@ -25,6 +25,16 @@
             "optional": true,
             "description": "The browser's cookies."

[lazyboy, 2017/02/15 21:45:27]

Add a note saying this will remove all cookies including session cookies and
persistent ones.

[lfg, 2017/02/15 22:44:01]

Done.

           },
+          "sessionCookies": {
+            "type": "boolean",
+            "optional": true,
+            "description": "The browser's session cookies."

[lazyboy, 2017/02/15 21:45:27]

Here and also for other places: replace browser's with WebSites', since this
applies to <webview> but not entire browser.

[lfg, 2017/02/15 22:44:01]

Done.

+          },
+          "persistentCookies": {
+            "type": "boolean",
+            "optional": true,
+            "description": "The browser's persistent cookies."
+          },
           "fileSystems": {
             "type": "boolean",
             "optional": true,