Replace System.getProperty('line.separator') with System.lineSeparator().

Resolves signalapp#13768

Author: GrzegorzBobryk

app/src/main/java/org/thoughtcrime/securesms/logsubmit/LogSectionLogcat.java

@@ -21,7 +21,7 @@ public class LogSectionLogcat implements LogSection {
       final Process        process        = Runtime.getRuntime().exec("logcat -d");
       final BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream()));
       final StringBuilder  log            = new StringBuilder();
-      final String         separator      = System.getProperty("line.separator");
+      final String         separator      = System.lineSeparator();
 
       String line;
       while ((line = bufferedReader.readLine()) != null) {

core-util-jvm/src/main/java/org/signal/core/util/Hex.java

@@ -14,7 +14,7 @@ public class Hex {
   private final static int HEX_DIGITS_START = 10;
   private final static int ASCII_TEXT_START = HEX_DIGITS_START + (16*2 + (16/2));
 
-  final static String EOL = System.getProperty("line.separator");
+  final static String EOL = System.lineSeparator();
 
   private final static char[] HEX_DIGITS = {
     '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'

libsignal-service/src/main/java/org/whispersystems/signalservice/internal/util/Hex.java

@@ -16,7 +16,7 @@ public class Hex {
   private final static int HEX_DIGITS_START = 10;
   private final static int ASCII_TEXT_START = HEX_DIGITS_START + (16*2 + (16/2));
 
-  final static String EOL = System.getProperty("line.separator");
+  final static String EOL = System.lineSeparator();
 
   private final static char[] HEX_DIGITS = {
     '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'