text: add support for invoke_action request

Add a request to be called by the client when the word currently being
composed is tapped by the user. Input methods often use this information
to offer more word suggestions to the user.

Signed-off-by: Jan Arne Petersen <jpetersen@openismus.com>

protocol/input-method.xml

@@ -127,6 +127,10 @@
       <arg name="hint" type="uint"/>
       <arg name="purpose" type="uint"/>
     </event>
+    <event name="invoke_action">
+      <arg name="button" type="uint"/>
+      <arg name="index" type="uint"/>
+    </event>
   </interface>
 
   <interface name="input_method" version="1">

protocol/text.xml

@@ -135,6 +135,10 @@
       <arg name="hint" type="uint"/>
       <arg name="purpose" type="uint"/>
     </request>
+    <request name="invoke_action">
+      <arg name="button" type="uint"/>
+      <arg name="index" type="uint"/>
+    </request>
     <event name="commit_string">
       <description summary="commit">
         Notify when text should be inserted into the editor widget. The text

src/text-backend.c

@@ -248,6 +248,22 @@ text_model_set_content_type(struct wl_client *client,
 	}
 }
 
+static void
+text_model_invoke_action(struct wl_client *client,
+			 struct wl_resource *resource,
+			 uint32_t button,
+			 uint32_t index)
+{
+	struct text_model *text_model = resource->data;
+	struct input_method *input_method, *next;
+
+	wl_list_for_each_safe(input_method, next, &text_model->input_methods, link) {
+		if (!input_method->context)
+			continue;
+		input_method_context_send_invoke_action(&input_method->context->resource, button, index);
+	}
+}
+
 static const struct text_model_interface text_model_implementation = {
 	text_model_set_surrounding_text,
 	text_model_activate,
@@ -255,7 +271,8 @@ static const struct text_model_interface text_model_implementation = {
 	text_model_reset,
 	text_model_set_micro_focus,
 	text_model_set_preedit,
-	text_model_set_content_type
+	text_model_set_content_type,
+	text_model_invoke_action
 };
 
 static void text_model_factory_create_text_model(struct wl_client *client,