Cache JNI call results in SysUtils on native side.

base/android/sys_utils.cc

Index: base/android/sys_utils.cc
diff --git a/base/android/sys_utils.cc b/base/android/sys_utils.cc
index 103324d95da36c6e091325857e39f9f4ff8bd864..efd13df3d42e814772987f93c66e81094294e0ad 100644
--- a/base/android/sys_utils.cc
+++ b/base/android/sys_utils.cc
@@ -15,16 +15,26 @@ bool SysUtils::Register(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
-bool SysUtils::IsLowEndDevice() {
+bool SysUtils::IsLowEndDeviceFromJni() {
   JNIEnv* env = AttachCurrentThread();
   return Java_SysUtils_isLowEndDevice(env);
 }
 
-size_t SysUtils::AmountOfPhysicalMemoryKB() {
+bool SysUtils::IsLowEndDevice() {
+  static bool is_low_end = IsLowEndDeviceFromJni();
+  return is_low_end;
+}
+
+size_t SysUtils::AmountOfPhysicalMemoryKBFromJni() {
   JNIEnv* env = AttachCurrentThread();
   return static_cast<size_t>(Java_SysUtils_amountOfPhysicalMemoryKB(env));
 }
 
+size_t SysUtils::AmountOfPhysicalMemoryKB() {
+  static size_t amount_of_ram = AmountOfPhysicalMemoryKBFromJni();
+  return amount_of_ram;
+}
+
 SysUtils::SysUtils() { }
 
 }  // namespace android