Add events for configuring and adding new providers to FSP API.

chrome/common/extensions/api/file_system_provider.idl

Index: chrome/common/extensions/api/file_system_provider.idl
diff --git a/chrome/common/extensions/api/file_system_provider.idl b/chrome/common/extensions/api/file_system_provider.idl
index 0b589617243fe5d7862ad3ceaa4d8b06f691329d..e0584f2e3c7fb886d6eed2336b702f3dd9f53403 100644
--- a/chrome/common/extensions/api/file_system_provider.idl
+++ b/chrome/common/extensions/api/file_system_provider.idl
@@ -44,7 +44,7 @@ namespace fileSystemProvider {
   // Source of the file system data.
   enum FileSystemSource {
     // The file system is handling a file, eg. an archive file obtained via the
-    // <code>OnLaunched</code> event and the <code>file_handlers</code> manifest
+    // <code>onLaunched</code> event and the <code>file_handlers</code> manifest
     // entry.
     FILE,
 
@@ -171,6 +171,8 @@ namespace fileSystemProvider {
   dictionary UnmountRequestedOptions {
     // The identifier of the file system to be unmounted.
     DOMString fileSystemId;
+
+    // The unique identifier of this request.
     long requestId;
   };
 
@@ -432,6 +434,15 @@ namespace fileSystemProvider {
     DOMString? tag;
   };
 
+  // Options for the <code>onConfigureRequested()</code> event.
+  dictionary ConfigureRequestedOptions {
+    // The identifier of the file system to be configured.
+    DOMString fileSystemId;
+
+    // The unique identifier of this request.
+    long requestId;
+  };
+
   // Callback to receive the result of getAll() function.
   callback GetAllCallback = void(FileSystemInfo[] fileSystems);
 
@@ -647,6 +658,21 @@ namespace fileSystemProvider {
         ProviderSuccessCallback successCallback,
         ProviderErrorCallback errorCallback);
 
+    // Raised when showing a configuration dialog for <code>fileSystemId</code>
+    // is requested. If it's not supported, then this event must not be handled.
+    [maxListeners=1] static void onConfigureRequested(

[benwells, 2015/04/16 00:29:35]

Should this be nodoc until the implementation is real?

[mtomasz, 2015/04/16 01:07:28]

This is going to be shipped in M44. I can add [nodoc], but there is already
updated documentation in fileBrowserPrivate.html which refers to these methods.
I could revert that documentation changes and add [nodoc] if you prefer.

[benwells, 2015/04/16 01:15:32]

Having documentation for new things that work is fine, as the documentation
should make it clear that the new thing is only available in whatever release it
comes in. As these functions are currently unimplemented / half implemented
(that's my understanding) they shouldn't be documented anywhere. If they are,
some poor developer will think the API is ready on dev channel and try to use
it.

Does that make sense?

[mtomasz, 2015/04/16 01:24:16]

Makes sense. I reverted the documentation and added nodoc.

+        ConfigureRequestedOptions options,
+        ProviderSuccessCallback successCallback,
+        ProviderErrorCallback errorCallback);
+
+    // Raised when showing a dialog for mounting a new file system is requested.
+    // If the extension/app is a file handler, then this event shouldn't be
+    // handled. Instead <code>onLaunched</code> should be handled in order to
+    // mount new file systems when a file is opened.
+    [maxListeners=1] static void onMountRequested(
+        ProviderSuccessCallback successCallback,

[benwells, 2015/04/16 00:29:36]

What about options? I'd have thought providing options to this (e.g. url for a
web based file system) makes sense.

[mtomasz, 2015/04/16 01:07:28]

It's responsibility of the providing extension to ask user for details such as
urls, credentials, ports, captchas, etc. As the options are different for each
providing extension, we decided to put the responsibility to show the UI on
providing extensions, rather than to try to create some general purpose dialog
on the File System Provider API implementation side.

In most cases, for onMountRequest providing extensions will show a dialog for
credentials/urls and whatever is required to make a mount. onConfigureRequested
will show the same dialog but with prefilled fields for already mounted file
system.

+        ProviderErrorCallback errorCallback);
+
     // Raised when setting a new directory watcher is requested. If an error
     // occurs, then <code>errorCallback</code> must be called.
     [maxListeners=1, nodoc] static void onAddWatcherRequested(