[ChromeOS] Do not send the memory pressure notification from chrome to renderers

chrome/browser/memory/tab_manager.cc

Index: chrome/browser/memory/tab_manager.cc
diff --git a/chrome/browser/memory/tab_manager.cc b/chrome/browser/memory/tab_manager.cc
index 096a786cf67963497b9fc99a1f5c7f4699d3265d..28397547c5576d44be0d5297bef3aa755e74a1ae 100644
--- a/chrome/browser/memory/tab_manager.cc
+++ b/chrome/browser/memory/tab_manager.cc
@@ -671,8 +671,12 @@ void TabManager::OnMemoryPressure(
   // NOTE: This mechanism relies on having a MemoryPressureMonitor
   // implementation that supports "CurrentPressureLevel". This is true on all
   // platforms on which TabManager is used.
+#if !defined(OS_CHROMEOS)
+  // Running GC under memory pressure can cause thrashing. Disable it on
+  // ChromeOS until the thrashing is fixed. crbug.com/588172.
   if (!under_memory_pressure_)
     DoChildProcessDispatch();
+#endif
 }
 
 bool TabManager::IsMediaTab(WebContents* contents) const {