https://bugs.webkit.org/show_bug.cgi?id=78491

Reviewed by Martin Robinson.

Add a new public class to the API, WebKitFileChooserRequest, to be
emitted along with a new WebKitWebView::run-file-chooser signal to
let client applications to provide their own file chooser dialog
when the use interacts with HTML Input elements of type 'file'.

* GNUmakefile.am: Added new source files and headers.
* UIProcess/API/gtk/WebKitFileChooserRequest.cpp: Added.
(_WebKitFileChooserRequestPrivate):
(webkit_file_chooser_request_init):
(webkitFileChooserRequestFinalize):
(webkitFileChooserRequestGetProperty):
(webkit_file_chooser_request_class_init):
(webkitFileChooserRequestCreate):
(webkit_file_chooser_request_get_mime_types):
(webkit_file_chooser_request_get_mime_types_filter):
(webkit_file_chooser_request_get_select_multiple):
(webkit_file_chooser_request_select_files):
(webkit_file_chooser_request_get_selected_files):
(webkit_file_chooser_request_cancel):
* UIProcess/API/gtk/WebKitFileChooserRequest.h: Added.
(_WebKitFileChooserRequest):
(_WebKitFileChooserRequestClass):
* UIProcess/API/gtk/WebKitFileChooserRequestPrivate.h: Added,
containing the prototype of webkitFileChooserRequestCreate.

Provide private API to make a file chooser request from the
WebView, and provide a default handler for it.

* UIProcess/API/gtk/WebKitWebView.cpp:
(fileChooserDialogResponseCallback): Handler for the 'response'
signal for the GtkFileChooserDialog used in the default
handler. It will call to webkit_file_chooser_request_select_files
or webkit_file_chooser_request_cancel as needed.
(webkitWebViewRunFileChooser): Default handler for the new
'run-file-chooser' signal. It will create a GtkFileChooserDialog,
connect to the 'response' signal and show it.
(webkit_web_view_class_init): Connect the 'run-file-chooser'
signal to the default handler, webkitWebViewRunFileChooser.
(webkitWebViewRunFileChooserRequest):
* UIProcess/API/gtk/WebKitWebView.h:
(_WebKitWebViewClass): Added prototype for the handler of the new
'run-file-chooser' signal.
* UIProcess/API/gtk/WebKitWebViewPrivate.h: Added prototype for
private new function webkitWebViewRunFileChooserRequest.

Provide an implementation for runOpenPanel in WebKitUIClient.

* UIProcess/API/gtk/WebKitUIClient.cpp:
(runOpenPanel): New, implements runOpenPanel by creating an
instance of WebKitFileChooserRequest and asking the WebView to
emit the 'run-file-chooser' signal with it.
(attachUIClientToView): Reference the new runOpenPanel function.

Added the new publich header to the main header.

* UIProcess/API/gtk/webkit2.h: Added WebKitFileChooserRequest.h.

New unit tests for the new WebKitFileChooserRequest API. Also,
extended the WebViewTest class to allow simulating mouse clicks.

* UIProcess/API/gtk/tests/TestWebKitWebView.cpp:
(checkMimeTypeForFilter): New, checks whether a GtkFileFilter
filters a given MIME type, as specified by RFC 2046.
(testWebViewFileChooserRequest): New unit test.
(beforeAll): Add the new unit test as an UIClientTest.

* UIProcess/API/gtk/tests/WebViewTest.cpp:
(WebViewTest::clickMouseButton): New public function to simulate a
mouse click through GdkEvents, as the combination of a 'press' and
a 'release' event. Used from the new unit test to simulate the
user pressing in the button rendered for a HTML Input element.
(WebViewTest::executeMouseButtonEvent): New private function to
simulate a mouse event through GdkEvents.
* UIProcess/API/gtk/tests/WebViewTest.h:

Updated documentation related files with the new API.

* UIProcess/API/gtk/docs/webkit2gtk-sections.txt: Added new API.
* UIProcess/API/gtk/docs/webkit2gtk-docs.sgml: Added new section.
* UIProcess/API/gtk/docs/webkit2gtk.types: Added get_type function.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@115627 268f45cc-cd09-0410-ab3c-d52691b4dbfc