<webview>: First stab at implementing media permission request for guests.

chrome/renderer/extensions/dispatcher.cc

Index: chrome/renderer/extensions/dispatcher.cc
diff --git a/chrome/renderer/extensions/dispatcher.cc b/chrome/renderer/extensions/dispatcher.cc
index 94a90d6dd15e027f56171962a0c3e7041b9f7f32..8e944be8ddb51d4d055cc06f98d4827a1903c10d 100644
--- a/chrome/renderer/extensions/dispatcher.cc
+++ b/chrome/renderer/extensions/dispatcher.cc
@@ -695,6 +695,8 @@ void Dispatcher::PopulateSourceMap() {
   // Platform app sources that are not API-specific..
   source_map_.RegisterSource("tagWatcher", IDR_TAG_WATCHER_JS);
   source_map_.RegisterSource("webview", IDR_WEB_VIEW_JS);
+  source_map_.RegisterSource("webview.experimentalAPI",
+                             IDR_WEB_VIEW_EXPERIMENTAL_API_JS);
   source_map_.RegisterSource("denyWebview", IDR_WEB_VIEW_DENY_JS);
   source_map_.RegisterSource("platformApp", IDR_PLATFORM_APP_JS);
   source_map_.RegisterSource("injectAppTitlebar", IDR_INJECT_APP_TITLEBAR_JS);
@@ -828,6 +830,10 @@ void Dispatcher::DidCreateScriptContext(
   if (context_type == Feature::BLESSED_EXTENSION_CONTEXT) {
     bool has_permission = extension->HasAPIPermission(APIPermission::kWebView);
     module_system->Require(has_permission ? "webview" : "denyWebview");
+    if (has_permission &&
+        extension->HasAPIPermission(APIPermission::kExperimental)) {

[Matt Perry, 2013/02/13 23:20:08]

We actually deprecated the "experimental" permission. Instead, we use
chrome/common/extensions/api/_permission_features.json to restrict certain APIs
to the "dev" channel. Once it's not an experiment anymore, then we release it to
the stable channel.

But after thinking about this, it seems like it won't work for your use case. We
want "webview" to have additional features on dev-channel only. There's no
official support for that, but you can use
  |Feature::GetCurrentChannel() < chrome::VersionInfo::CHANNEL_DEV|
for now. If that's true, automatically add "webview.experimental" (I'd drop the
"API").

[lazyboy, 2013/02/14 00:09:46]

OK thanks.
btw, I'm assuming you meant <= CHANNEL_DEV.
Done.

[Matt Perry, 2013/02/14 00:22:47]

Woops, good catch.

+      module_system->Require("webview.experimentalAPI");
+    }
   }
 
   context->set_module_system(module_system.Pass());