Enable TabManager to kill foreground Android apps.

chrome/browser/memory/tab_manager_delegate_chromeos.cc

Index: chrome/browser/memory/tab_manager_delegate_chromeos.cc
diff --git a/chrome/browser/memory/tab_manager_delegate_chromeos.cc b/chrome/browser/memory/tab_manager_delegate_chromeos.cc
index 2d6e2866180e69f65fe8d8712addb532d5da5a5c..a422b434496dc60a71ce9a2f533af1b5c9168d07 100644
--- a/chrome/browser/memory/tab_manager_delegate_chromeos.cc
+++ b/chrome/browser/memory/tab_manager_delegate_chromeos.cc
@@ -593,11 +593,11 @@ void TabManagerDelegate::LowMemoryKillImpl(
   // backwards.
   for (auto it = candidates.rbegin(); it != candidates.rend(); ++it) {
     VLOG(3) << "Target memory to free: " << target_memory_to_free_kb << " KB";
-    // Never kill selected tab or Android foreground app, regardless whether
-    // they're in the active window. Since the user experience would be bad.
+    // Never kill selected tab to align with the behavior in other platforms.
+    // Note that non-focused Android apps are prone to be killed, however,
+    // regardless of their visibility.
     ProcessType process_type = it->process_type();
-    if (process_type == ProcessType::VISIBLE_APP ||
-        process_type == ProcessType::FOCUSED_APP ||
+    if (process_type == ProcessType::FOCUSED_APP ||
         process_type == ProcessType::FOCUSED_TAB) {
       VLOG(2) << "Skipped killing " << *it;
       continue;