Add PlatformWindow/Event related code for Ozone X11.

The bigger changes here are to X11EventSource and X11Window. For both
classes the current implementation is for PlatformEvent=XEvent* but with
Ozone PlatformEvent=void*=ui::Event*. Most of the implementation will be
the same between X11 and Ozone X11 otherwise. Both classes have been split
into a shared base class and compile specific implementation.

X11EventSource is now the base class. There were two possible listener
implementations, Glib vs Libevent, with Libevent being unused so far. The
X11 implementation is X11EventSourceGlib and uses Glib. The Ozone X11
implementation is X11EventSourceLibevent and uses Libevent. Since the Ozone
X11 implementation is dispatching ui::Events there is a separate dispatcher
list for XEventDispatchers added to send XEvents where necessary.

X11WindowBase is now the base class. The X11 implementation is still called
X11Window. The X11 Ozone implementation is X11WindowOzone. The X11 Ozone
version registers itself as both a PlatformEventDispatcher and
XEventDispatcher.

Compile with the following gn args:
use_ozone = true
ozone_platform_x11 = true
target_os = "chromeos"

TBR=rockot@chromium.org
BUG=361137

Review URL: https://codereview.chromium.org/1602173005

Cr-Commit-Position: refs/heads/master@{#374502}

1 files changed, 2 insertions, 2 deletions

diff --git a/ui/base/dragdrop/os_exchange_data_provider_aurax11_unittest.cc b/ui/base/dragdrop/os_exchange_data_provider_aurax11_unittest.cc
index 457ba6b..90fa7c2 100644
--- a/ui/base/dragdrop/os_exchange_data_provider_aurax11_unittest.cc
+++ b/ui/base/dragdrop/os_exchange_data_provider_aurax11_unittest.cc
@@ -13,7 +13,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/dragdrop/file_info.h"
-#include "ui/events/platform/x11/x11_event_source.h"
+#include "ui/events/platform/x11/x11_event_source_glib.h"
 #include "url/gurl.h"
 
 const char kFileURL[] = "file:///home/user/file.txt";
@@ -39,7 +39,7 @@ class OSExchangeDataProviderAuraX11Test : public testing::Test {
 
  protected:
   base::MessageLoopForUI message_loop;
-  X11EventSource event_source;
+  X11EventSourceGlib event_source;
   ui::OSExchangeDataProviderAuraX11 provider;
 };