Add a message pump for touchui=1

The message pump reads events directly from X. For most events, it passes them
on to GDK for normal processing. It consumes some events (e.g. keypress events)
to demonstrate how it's intended to work. This, of course, makes chrome mostly
unusable since you can only use the mouse to do things. But this is a small
first step towards capturing events through MPX (e.g. touch etc.) and processing
them as chrome pleases.

glib message pump: Slightly change architecture

This changeset breaks down the glib message pump a little so that it can be
easily subclassed. The next set of commits will introduce a subclass that still
uses GTK and GDK widgets, but reads events directly from X instead of through
GTK/GDK.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=63397

Review URL: http://codereview.chromium.org/3748002
Patch from Sadrul Chowdhury <sadrul@chromium.org>.

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@63519 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 18 insertions, 12 deletions

diff --git a/base/message_pump_glib.cc b/base/message_pump_glib.cc
index e85a712..ad6d177 100644
--- a/base/message_pump_glib.cc
+++ b/base/message_pump_glib.cc
@@ -207,8 +207,7 @@ void MessagePumpForUI::RunWithDispatcher(Delegate* delegate,
     // Don't block if we think we have more work to do.
     bool block = !more_work_is_plausible;
 
-    // g_main_context_iteration returns true if events have been dispatched.
-    more_work_is_plausible = g_main_context_iteration(context_, block);
+    more_work_is_plausible = RunOnce(context_, block);
     if (state_->should_quit)
       break;
 
@@ -232,6 +231,11 @@ void MessagePumpForUI::RunWithDispatcher(Delegate* delegate,
   state_ = previous_state;
 }
 
+bool MessagePumpForUI::RunOnce(GMainContext* context, bool block) {
+  // g_main_context_iteration returns true if events have been dispatched.
+  return g_main_context_iteration(context, block);
+}
+
 // Return the timeout we want passed to poll.
 int MessagePumpForUI::HandlePrepare() {
   // We know we have work, but we haven't called HandleDispatch yet. Don't let
@@ -332,19 +336,21 @@ void MessagePumpForUI::ScheduleDelayedWork(const Time& delayed_work_time) {
   ScheduleWork();
 }
 
-// static
-void MessagePumpForUI::EventDispatcher(GdkEvent* event, gpointer data) {
-  MessagePumpForUI* message_pump = reinterpret_cast<MessagePumpForUI*>(data);
-
-  message_pump->WillProcessEvent(event);
-  if (message_pump->state_ &&  // state_ may be null during tests.
-      message_pump->state_->dispatcher) {
-    if (!message_pump->state_->dispatcher->Dispatch(event))
-      message_pump->state_->should_quit = true;
+void MessagePumpForUI::DispatchEvents(GdkEvent* event) {
+  WillProcessEvent(event);
+  if (state_ && state_->dispatcher) { // state_ may be null during tests.
+    if (!state_->dispatcher->Dispatch(event))
+      state_->should_quit = true;
   } else {
     gtk_main_do_event(event);
   }
-  message_pump->DidProcessEvent(event);
+  DidProcessEvent(event);
+}
+
+// static
+void MessagePumpForUI::EventDispatcher(GdkEvent* event, gpointer data) {
+  MessagePumpForUI* message_pump = reinterpret_cast<MessagePumpForUI*>(data);
+  message_pump->DispatchEvents(event);
 }
 
 }  // namespace base