Fix various lint warnings (#4409)

- Remove empty file `ExampleInstrumentedTest.java`.
- Replace deprecated `MigrationTestHelper` constructor call.
- Add reified inline extension methods for `Bundle` and `Intent` to
retrieve `Parcelable` and `Serializable` objects by calling the core
`BundleCompat` and `IntentCompat` methods, to allow shorter syntax and
removing the need to pass the class explicitly.
- Replace deprecated `drawable.setColorFilter()` with simpler
`drawable.setTint()` (uses blend mode `SRC_IN` by default, has the same
effect as `SRC_ATOP` when the source is a color).
- Rename shadowed variables (mostly caught exceptions).
- Remove unnecessary `.orEmpty()` on non-null fields.
- Replace `.size() == 0` with `.isEmpty()`.
- Prevent `NullPointerException` when `account.getDisplayName()` is
`null` in `StatusBaseViewHolder.setDisplayName()`.
- Declare `customEmojis` argument as non-null in
`StatusBaseViewHolder.setDisplayName()` because it calls
`CustomEmojiHelper.emojify()` which now requires it to be non-null.
- Prevent `NullPointerException` when no matching filter is found in
`StatusBaseViewHolder.setupFilterPlaceholder()`.
- Remove deprecated call to `setTargetFragment()` (target fragment is
not used anyway).
- Remove deprecated call to `isUserVisibleHint()` and test if the view
has been destroyed instead.
- Remove some unused imports.
- Remove unnecessary casts.
- Rename arguments to supertype names when a warning is shown.
- Prevent a potential memory leak by clearing the
`toolbarVisibilityDisposable` reference in `onDestroyView()`.

app/src/main/java/com/keylesspalace/tusky/service/SendStatusService.kt

@@ -31,7 +31,6 @@ import android.util.Log
 import androidx.annotation.StringRes
 import androidx.core.app.NotificationCompat
 import androidx.core.app.ServiceCompat
-import androidx.core.content.IntentCompat
 import at.connyduck.calladapter.networkresult.fold
 import com.keylesspalace.tusky.MainActivity
 import com.keylesspalace.tusky.R
@@ -52,6 +51,7 @@ import com.keylesspalace.tusky.entity.NewStatus
 import com.keylesspalace.tusky.entity.ScheduledStatus
 import com.keylesspalace.tusky.entity.Status
 import com.keylesspalace.tusky.network.MastodonApi
+import com.keylesspalace.tusky.util.getParcelableExtraCompat
 import com.keylesspalace.tusky.util.unsafeLazy
 import dagger.android.AndroidInjection
 import java.util.concurrent.ConcurrentHashMap
@@ -102,7 +102,7 @@ class SendStatusService : Service(), Injectable {
 
     override fun onStartCommand(intent: Intent, flags: Int, startId: Int): Int {
         if (intent.hasExtra(KEY_STATUS)) {
-            val statusToSend: StatusToSend = IntentCompat.getParcelableExtra(intent, KEY_STATUS, StatusToSend::class.java)
+            val statusToSend: StatusToSend = intent.getParcelableExtraCompat(KEY_STATUS)
                 ?: throw IllegalStateException("SendStatusService started without $KEY_STATUS extra")
 
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
@@ -247,11 +247,11 @@ class SendStatusService : Service(), Injectable {
                 scheduledAt = statusToSend.scheduledAt,
                 poll = statusToSend.poll,
                 language = statusToSend.language,
-                mediaAttributes = media.map { media ->
+                mediaAttributes = media.map { mediaItem ->
                     MediaAttribute(
-                        id = media.id!!,
-                        description = media.description,
-                        focus = media.focus?.toMastodonApiString(),
+                        id = mediaItem.id!!,
+                        description = mediaItem.description,
+                        focus = mediaItem.focus?.toMastodonApiString(),
                         thumbnail = null
                     )
                 }