Refactor ARC OOM handler code

chrome/browser/chromeos/arc/process/arc_process.cc

Index: chrome/browser/chromeos/arc/process/arc_process.cc
diff --git a/chrome/browser/chromeos/arc/process/arc_process.cc b/chrome/browser/chromeos/arc/process/arc_process.cc
index abb054a67c82ae8c9a0208f138eea0935f1e33cc..12b10044188e3e36532b838e1b38e9ee16a1b919 100644
--- a/chrome/browser/chromeos/arc/process/arc_process.cc
+++ b/chrome/browser/chromeos/arc/process/arc_process.cc
@@ -8,6 +8,15 @@
 
 namespace arc {
 
+namespace {
+
+// A special process on Android side which serves as a dummy "focused" app

[Yusuke Sato, 2017/05/09 22:54:35]

moved

+// when the focused window is a Chrome side window (i.e., all Android
+// processes are running in the background). We don't want to kill it anyway.
+static constexpr char kArcHomeProcess[] = "org.chromium.arc.home";

[Luis Héctor Chávez, 2017/05/09 23:00:10]

nit: static is superfluous in the anonymous namespace

[Yusuke Sato, 2017/05/09 23:20:12]

Done.

+
+}  // namespace
+
 ArcProcess::ArcProcess(base::ProcessId nspid,
                        base::ProcessId pid,
                        const std::string& process_name,
@@ -34,4 +43,17 @@ bool ArcProcess::operator<(const ArcProcess& rhs) const {
 ArcProcess::ArcProcess(ArcProcess&& other) = default;
 ArcProcess& ArcProcess::operator=(ArcProcess&& other) = default;
 
+bool ArcProcess::IsUserVisible() const {
+  return process_state() <= mojom::ProcessState::IMPORTANT_FOREGROUND ||
+         process_name() == kArcHomeProcess;
+}
+
+bool ArcProcess::IsKillableForKernel() const {
+  // Protect PERSISTENT, PERSISTENT_UI, and our HOME processes since they should
+  // never be killed even by the kernel. Returning false for them allows their
+  // OOM adjustment scores to remain negative.
+  return process_state() > arc::mojom::ProcessState::PERSISTENT_UI &&
+         process_name() != kArcHomeProcess;
+}
+
 }  // namespace arc