Add yet more GN isolates ...

ui/events/BUILD.gn

Index: ui/events/BUILD.gn
diff --git a/ui/events/BUILD.gn b/ui/events/BUILD.gn
index b2d2ec7910f5795b0599050ed12f4a0ee4945183..778497fbe12c3155da89b51dde41a6bca12b0e53 100644
--- a/ui/events/BUILD.gn
+++ b/ui/events/BUILD.gn
@@ -296,6 +296,15 @@ source_set("test_support") {
   }
 }
 
+# TODO(GYP): Delete this after we've converted everything to GN.
+# The _run targets exist only for compatibility w/ GYP.
+group("events_unittests_run") {
+  testonly = true
+  deps = [
+    ":events_unittests",
+  ]
+}
+
 test("events_unittests") {
   sources = [
     "android/scroller_unittest.cc",
@@ -340,6 +349,8 @@ test("events_unittests") {
     "//ui/gfx:test_support",
   ]
 
+  data_deps = [ "//third_party/mesa:osmesa" ]
+
   include_dirs = [ "//testing/gmock/include" ]
 
   if (use_x11) {