Move OneWriterSeqLock and SharedMemorySeqLockBuffer from content/ to device/base/synchronization

content/test/BUILD.gn

Index: content/test/BUILD.gn
diff --git a/content/test/BUILD.gn b/content/test/BUILD.gn
index 0adada204c9400bcd594c6e7a83a60bab173d962..51c8a85549557b2f1a2cdb11b302eba78916f5fa 100644
--- a/content/test/BUILD.gn
+++ b/content/test/BUILD.gn
@@ -227,6 +227,7 @@ static_library("test_support") {
     "//content/renderer:for_content_tests",
     "//content/shell:pak",
     "//content/utility:for_content_tests",
+    "//device/base/synchronization",
     "//device/geolocation",
     "//device/nfc:mojo_bindings",
     "//ipc:test_support",
@@ -722,6 +723,7 @@ test("content_browsertests") {
     "//content/shell:content_shell_lib",
     "//content/shell:pak",
     "//content/test:test_support",
+    "//device/base/synchronization",
     "//device/battery",
     "//device/battery:mojo_bindings",
     "//device/power_save_blocker",
@@ -1281,7 +1283,6 @@ test("content_unittests") {
     "../common/mac/font_descriptor_unittest.mm",
     "../common/manifest_util_unittest.cc",
     "../common/navigation_params_unittest.cc",
-    "../common/one_writer_seqlock_unittest.cc",
     "../common/origin_trials/trial_token_unittest.cc",
     "../common/origin_trials/trial_token_validator_unittest.cc",
     "../common/origin_util_unittest.cc",