Split cc/base into separate GN source_set and clean deps

cc/cc.gyp

Index: cc/cc.gyp
diff --git a/cc/cc.gyp b/cc/cc.gyp
index bc83b1ff42cc20c98413fc0c7c940a3e95a7e2a0..548e25ff55d974d9698e7df6fccc6f1b5ed1f71e 100644
--- a/cc/cc.gyp
+++ b/cc/cc.gyp
@@ -69,10 +69,6 @@
         'base/delayed_unique_notifier.h',
         'base/invalidation_region.cc',
         'base/invalidation_region.h',
-        'base/latency_info_swap_promise.cc',
-        'base/latency_info_swap_promise.h',
-        'base/latency_info_swap_promise_monitor.cc',
-        'base/latency_info_swap_promise_monitor.h',
         'base/math_util.cc',
         'base/math_util.h',
         'base/ref_counted_managed.h',
@@ -85,9 +81,6 @@
         'base/scoped_ptr_vector.h',
         'base/simple_enclosed_region.cc',
         'base/simple_enclosed_region.h',
-        'base/swap_promise.h',
-        'base/swap_promise_monitor.cc',
-        'base/swap_promise_monitor.h',
         'base/switches.cc',
         'base/switches.h',
         'base/synced_property.h',
@@ -293,6 +286,8 @@
         'output/gl_renderer.h',
         'output/gl_renderer_draw_cache.cc',
         'output/gl_renderer_draw_cache.h',
+        'output/latency_info_swap_promise.cc',
+        'output/latency_info_swap_promise.h',
         'output/managed_memory_policy.cc',
         'output/managed_memory_policy.h',
         'output/output_surface.cc',
@@ -323,6 +318,7 @@
         'output/software_renderer.h',
         'output/static_geometry_binding.cc',
         'output/static_geometry_binding.h',
+        'output/swap_promise.h',
         'output/viewport_selection_bound.cc',
         'output/viewport_selection_bound.h',
         'output/vsync_parameter_observer.h',
@@ -535,6 +531,8 @@
         'trees/damage_tracker.h',
         'trees/draw_property_utils.cc',
         'trees/draw_property_utils.h',
+        'trees/latency_info_swap_promise_monitor.cc',
+        'trees/latency_info_swap_promise_monitor.h',
         'trees/layer_tree_host.cc',
         'trees/layer_tree_host.h',
         'trees/layer_tree_host_client.h',
@@ -562,6 +560,8 @@
         'trees/scoped_abort_remaining_swap_promises.h',
         'trees/single_thread_proxy.cc',
         'trees/single_thread_proxy.h',
+        'trees/swap_promise_monitor.cc',
+        'trees/swap_promise_monitor.h',
         'trees/thread_proxy.cc',
         'trees/thread_proxy.h',
         'trees/tree_synchronizer.cc',