Idle Detection API: Prototype

https://github.com/inexorabletash/idle-detection

Just a webification of the chrome.idle.* APIs.

Does not yet include:

- permission checks
- android integration
- final API

Intent to implement:

https://groups.google.com/a/chromium.org/forum/#!topic/blink-dev/OuwzBmH02M4

Design doc:

https://docs.google.com/document/d/1_XlwY3NuG2HwWEYVrR-MNvw_i4hj5ZNj3gKvxWqO0FU/edit

Bug: 878979
Change-Id: Ie45b34d5c29e04dfe65f8ff5127c6be34850d68f
Reviewed-on: https://chromium-review.googlesource.com/c/1351490
Commit-Queue: Sam Goto <[email protected]>
Reviewed-by: Reilly Grant <[email protected]>
Reviewed-by: Mike West <[email protected]>
Reviewed-by: Pavel Feldman <[email protected]>
Reviewed-by: Jochen Eisinger <[email protected]>
Auto-Submit: Sam Goto <[email protected]>
Cr-Commit-Position: refs/heads/master@{#624304}
diff --git a/content/browser/BUILD.gn b/content/browser/BUILD.gn
index 43d2187..c8984723 100644
--- a/content/browser/BUILD.gn
+++ b/content/browser/BUILD.gn
@@ -942,6 +942,8 @@
     "histogram_synchronizer.h",
     "histograms_internals_ui.cc",
     "histograms_internals_ui.h",
+    "idle/idle_manager.cc",
+    "idle/idle_manager.h",
     "image_capture/image_capture_impl.cc",
     "image_capture/image_capture_impl.h",
     "indexed_db/cursor_impl.cc",