Revert of Resurrect Aura Linux accessibility.

build/linux/system.gyp

Index: build/linux/system.gyp
diff --git a/build/linux/system.gyp b/build/linux/system.gyp
index ed7f942fd68b8b578d2a514883da97d9844af0d2..a71a5c5927fa5d2bb777a8ec68f4a1b5f61858e6 100644
--- a/build/linux/system.gyp
+++ b/build/linux/system.gyp
@@ -91,30 +91,6 @@
       # added back to Chrome OS and Ozone. Don't try to use GTK on Chrome OS and Ozone.
       'targets': [
         {
-          'target_name': 'atk',
-          'type': 'none',
-          'conditions': [
-            ['_toolset=="target"', {
-              'direct_dependent_settings': {
-                'cflags': [
-                  '<!@(<(pkg-config) --cflags atk)',
-                ],
-                'defines': [
-                  'ATK_LIB_DIR="<!@(<(pkg-config) --variable=libdir atk)"',
-                ],
-              },
-              'link_settings': {
-                'ldflags': [
-                  '<!@(<(pkg-config) --libs-only-L --libs-only-other atk)',
-                ],
-                'libraries': [
-                  '<!@(<(pkg-config) --libs-only-l atk)',
-                ],
-              },
-            }],
-          ],
-        },
-        {
           'target_name': 'gdk',
           'type': 'none',
           'conditions': [