Expand is_linux to is_linux || is_chromeos.

Currently is_linux is set to true on Chrome OS build,
but it is planned to set false. This is the preparation
to keep the compatibility.

Bug: 1110266
Test: Built locally.
Change-Id: I398d3fb69f918d079a863c23971518ae0341f63e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2405753Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Ted Meyer <tmathmeyer@chromium.org>
Commit-Queue: Hidehiko Abe <hidehiko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#806459}

media/media_options.gni

@@ -148,8 +148,8 @@ declare_args() {
 # will be hosted in the mojo CDM service running in the CDM (utility) process.
 # On Fuchsia, this is only enabled to build libclearkeycdm.so, the mojo CDM
 # service is not used.
-enable_library_cdms =
-    (is_linux && !is_chromecast) || is_mac || is_win || is_fuchsia
+enable_library_cdms = (is_linux && !is_chromecast) || is_chromeos || is_mac ||
+                      is_win || is_fuchsia
 
 declare_args() {
   # When enabled, this feature allows developers to use a runtime flag to

ui/aura/BUILD.gn

@@ -247,7 +247,7 @@ static_library("test_support") {
     sources += [ "test/ui_controls_factory_aurawin.cc" ]
   }
 
-  if (is_linux) {
+  if (is_linux || is_chromeos) {
     sources += [ "test/ui_controls_factory_aura_linux.cc" ]
   }
 

ui/compositor/BUILD.gn

@@ -226,7 +226,7 @@ static_library("test_support") {
     ]
   }
 
-  if (is_linux) {
+  if (is_linux || is_chromeos) {
     sources += [ "test/test_compositor_host_linux.cc" ]
   }
 }