Cache JNI call results in SysUtils on native side.

BUG=323727

Review URL: https://codereview.chromium.org/89773002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238228 0039d316-1c4b-4281-b951-d872f2087c98

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

base/android/sys_utils.h

@@ -22,6 +22,9 @@ class BASE_EXPORT SysUtils {
 
  private:
   SysUtils();
+
+  static bool IsLowEndDeviceFromJni();
+  static size_t AmountOfPhysicalMemoryKBFromJni();
 };
 
 }  // namespace android