Add Xlib support to viewer

gyp/viewer.gyp

 # Copyright 2016 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 # GYP file to build performance testbench.
 #
 {
   'includes': [
     'apptype_console.gypi',
   ],
   'targets': [
     {
       'target_name': 'viewer',
       'type': 'executable',
       'includes' : [
         'gmslides.gypi',
       ],
       'include_dirs': [
         '../bench',
         '../gm',
         '../include/views',
         '../include/private',
         '../src/core',
         '../src/effects',
         '../src/gpu',
         '../src/images',
         '../src/image',
+        '../src/views/unix',
         '../tools/timer',
       ],
       'sources': [
         '../gm/gm.cpp',
         '../src/views/SkTouchGesture.cpp',
+        '../src/views/unix/keysym2ucs.c',
         '<!@(python find.py ../tools/viewer "*.cpp")',
       ],
       'dependencies': [
         'flags.gyp:flags',
         'gputest.gyp:skgputest',
         'jsoncpp.gyp:jsoncpp',
         'skia_lib.gyp:skia_lib',
         'tools.gyp:crash_handler',
         'tools.gyp:proc_stats',
         'tools.gyp:resources',
         'tools.gyp:sk_tool_utils',
         'tools.gyp:timer',
         'tools.gyp:url_data_manager',
       ],
       'conditions' : [
         [ 'skia_os == "android"', {
           'dependencies': [
             'android_deps.gyp:Android_EntryPoint',
             'android_deps.gyp:native_app_glue',
           ],
           'link_settings': {
             'libraries': [
               '-landroid',
             ],
           },
         }],
+        [ 'skia_os == "linux"', {
+          'link_settings': {
+            'libraries': [
+              '-lX11-xcb',
+            ],
+          },
+        }],
         ['skia_os != "android"', {
           'sources/': [ ['exclude', '_android.(h|cpp)$'],
           ],
         }],
+        ['skia_os != "linux"', {
+          'sources/': [ 
+            ['exclude', '_unix.(h|cpp)$'],
+            ['exclude', 'keysym2ucs.c'],
+          ],
+        }],
         ['skia_os != "win"', {
           'sources/': [ ['exclude', '_win.(h|cpp)$'],
           ],
         }],
       ],
     },
   ],
 }