Added memory-monitor for ChromeOS.

content/browser/BUILD.gn

Index: content/browser/BUILD.gn
diff --git a/content/browser/BUILD.gn b/content/browser/BUILD.gn
index 374866d381ccc69db39d03d29f4592fad6abc4e8..99702828557813d3443a2b89de35c4fb4f1b8776 100644
--- a/content/browser/BUILD.gn
+++ b/content/browser/BUILD.gn
@@ -867,8 +867,6 @@ source_set("browser") {
     "memory/memory_message_filter.h",
     "memory/memory_monitor.cc",
     "memory/memory_monitor.h",
-    "memory/memory_monitor_linux.cc",
-    "memory/memory_monitor_linux.h",
     "memory/memory_monitor_win.cc",
     "memory/memory_monitor_win.h",
     "memory/memory_pressure_controller_impl.cc",
@@ -1383,6 +1381,19 @@ source_set("browser") {
     deps += [ "//ui/events" ]
   }
 
+  # ChromeOS also defines linux but their memory-monitors conflict.
+  if (is_chromeos) {
+    sources += [
+      "memory/memory_monitor_chromeos.cc",
+      "memory/memory_monitor_chromeos.h",
+    ]
+  } else {
+    sources += [
+      "memory/memory_monitor_linux.cc",
+      "memory/memory_monitor_linux.h",
+    ]
+  }
+
   if (!is_win) {
     sources += [
       "file_descriptor_info_impl.cc",