dpwa: Move OsIntegrationManager to web_applications:common gn node.

web_applications:common subsystems are common for
web_applications:web_applications and web_applications:extensions.

Bug: 1098027
Change-Id: I61ae6777459dd58c389cd0f716dfc067c5de2824
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2309491
Auto-Submit: Alexey Baskakov <loyso@chromium.org>
Commit-Queue: Daniel Murphy <dmurph@chromium.org>
Reviewed-by: Daniel Murphy <dmurph@chromium.org>
Cr-Commit-Position: refs/heads/master@{#790468}

chrome/browser/web_applications/BUILD.gn

@@ -22,6 +22,8 @@ source_set("common") {
     "manifest_update_manager.h",
     "manifest_update_task.cc",
     "manifest_update_task.h",
+    "os_integration_manager.cc",
+    "os_integration_manager.h",
     "system_web_app_manager.cc",
     "system_web_app_manager.h",
     "web_app_tab_helper.cc",
@@ -58,8 +60,6 @@ source_set("web_applications") {
     "external_web_app_manager.h",
     "file_utils_wrapper.cc",
     "file_utils_wrapper.h",
-    "os_integration_manager.cc",
-    "os_integration_manager.h",
     "pending_app_install_task.cc",
     "pending_app_install_task.h",
     "pending_app_manager_impl.cc",