global: Cleanup line lengths and misc lint warnings

I know we decided to ditch the idea of shutting up "Exception
thrown with empty param" warnings but this pesters me too
much and we can instead just treat this as a weird future proofing
thing if and when we end up needing the exception messages.

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

app/src/main/java/com/wireguard/android/util/ClipboardUtils.java

@@ -19,6 +19,7 @@ import android.widget.TextView;
 
 public final class ClipboardUtils {
     private ClipboardUtils() {
+        // Prevent instantiation
     }
 
     public static void copyTextView(final View view) {

app/src/main/java/com/wireguard/android/util/ObservableKeyedArrayList.java

@@ -25,28 +25,28 @@ public class ObservableKeyedArrayList<K, E extends Keyed<? extends K>>
     @Override
     public boolean add(final E e) {
         if (e == null)
-            throw new NullPointerException();
+            throw new NullPointerException("Trying to add a null element");
         return super.add(e);
     }
 
     @Override
     public void add(final int index, final E e) {
         if (e == null)
-            throw new NullPointerException();
+            throw new NullPointerException("Trying to add a null element");
         super.add(index, e);
     }
 
     @Override
     public boolean addAll(@NonNull final Collection<? extends E> c) {
         if (c.contains(null))
-            throw new NullPointerException();
+            throw new NullPointerException("Trying to add a collection with null element(s)");
         return super.addAll(c);
     }
 
     @Override
     public boolean addAll(final int index, @NonNull final Collection<? extends E> c) {
         if (c.contains(null))
-            throw new NullPointerException();
+            throw new NullPointerException("Trying to add a collection with null element(s)");
         return super.addAll(index, c);
     }
 
@@ -100,7 +100,7 @@ public class ObservableKeyedArrayList<K, E extends Keyed<? extends K>>
     @Override
     public E set(final int index, final E e) {
         if (e == null)
-            throw new NullPointerException();
+            throw new NullPointerException("Trying to set a null key");
         return super.set(index, e);
     }
 }

app/src/main/java/com/wireguard/android/util/ObservableSortedKeyedArrayList.java

@@ -95,7 +95,9 @@ public class ObservableSortedKeyedArrayList<K, E extends Keyed<? extends K>>
     @Override
     public K firstKey() {
         if (isEmpty())
-            throw new NoSuchElementException();
+            // The parameter in the exception is only to shut
+            // lint up, we never care for the exception message.
+            throw new NoSuchElementException("Empty set");
         return get(0).getKey();
     }
 
@@ -137,7 +139,9 @@ public class ObservableSortedKeyedArrayList<K, E extends Keyed<? extends K>>
     @Override
     public K lastKey() {
         if (isEmpty())
-            throw new NoSuchElementException();
+            // The parameter in the exception is only to shut
+            // lint up, we never care for the exception message.
+            throw new NoSuchElementException("Empty set");
         return get(size() - 1).getKey();
     }
 

app/src/main/java/com/wireguard/android/util/RootShell.java

@@ -50,7 +50,7 @@ public class RootShell {
         final File cacheDir = context.getCacheDir();
         localBinaryDir = new File(cacheDir, "bin");
         localTemporaryDir = new File(cacheDir, "tmp");
-        preamble = String.format("export CALLING_PACKAGE=com.wireguard.android; export PATH=\"%s:$PATH\" TMPDIR='%s'; id -u\n",
+        preamble = String.format("export CALLING_PACKAGE=com.wireguard.android PATH=\"%s:$PATH\" TMPDIR='%s'; id -u\n",
                 localBinaryDir, localTemporaryDir);
     }