Refactor OS_LINUX preprocessor directive for LaCrOS effort.

Currently, ChromeOS defines the OS_LINUX directive as well as
OS_CHROMEOS.  We're working to separate these two, so we're
making the fact that OS_LINUX == OS_LINUX || OS_CHROMEOS
explicit.

This is changes for /chrome/browser/ui/views/web_apps

This CL was uploaded by git cl split.

R=mgiuca@chromium.org

Bug: 1110266
Change-Id: I452196d7fb9de8634c2c8b6044d9b0bafb4691ab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2371282Reviewed-by: Alan Cutter <alancutter@chromium.org>
Commit-Queue: Sean McAllister <smcallis@google.com>
Cr-Commit-Position: refs/heads/master@{#803501}

chrome/browser/ui/views/web_apps/pwa_confirmation_bubble_view.cc

@@ -33,7 +33,8 @@
 
 namespace {
 
-#if defined(OS_WIN) || defined(OS_MAC) || defined(OS_LINUX)
+#if defined(OS_WIN) || defined(OS_MAC) || defined(OS_LINUX) || \
+    defined(OS_CHROMEOS)
 constexpr char kDeviceTypeForCheckbox[] = "computer";
 #else
 constexpr char kDeviceTypeForCheckbox[] = "other";