Issue mozilla-mobile#2346: Fix warnings in concept-engine.

Author: pocmo

buildSrc/src/main/java/KotlinCompiler.kt

@@ -23,7 +23,6 @@ object KotlinCompiler {
         "browser-search",
         "browser-storage-sync",
         "browser-toolbar",
-        "concept-engine",
         "concept-toolbar",
         "feature-accounts",
         "feature-awesomebar",

components/concept/engine/build.gradle

@@ -35,6 +35,7 @@ dependencies {
     api project(':support-base')
     api project(':browser-errorpages')
 
+    testImplementation Dependencies.androidx_test_core
     testImplementation Dependencies.testing_junit
     testImplementation Dependencies.testing_robolectric
     testImplementation Dependencies.testing_mockito

components/concept/engine/src/test/java/mozilla/components/concept/engine/EngineViewTest.kt

@@ -7,20 +7,23 @@ package mozilla.components.concept.engine
 import android.content.Context
 import android.graphics.Bitmap
 import android.widget.FrameLayout
+import androidx.test.core.app.ApplicationProvider
 import org.junit.Assert.assertTrue
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.mockito.Mockito.spy
 import org.mockito.Mockito.verify
 import org.robolectric.RobolectricTestRunner
-import org.robolectric.RuntimeEnvironment
 import java.lang.ClassCastException
 
 @RunWith(RobolectricTestRunner::class)
 class EngineViewTest {
+    private val context: Context
+        get() = ApplicationProvider.getApplicationContext()
+
     @Test
     fun `asView method returns underlying Android view`() {
-        val engineView = createDummyEngineView(RuntimeEnvironment.application)
+        val engineView = createDummyEngineView(context)
 
         val view = engineView.asView()
 
@@ -35,7 +38,7 @@ class EngineViewTest {
 
     @Test
     fun lifecycleObserver() {
-        val engineView = spy(createDummyEngineView(RuntimeEnvironment.application))
+        val engineView = spy(createDummyEngineView(context))
         val observer = LifecycleObserver(engineView)
 
         observer.onCreate()
@@ -59,7 +62,7 @@ class EngineViewTest {
 
     private fun createDummyEngineView(context: Context): EngineView = DummyEngineView(context)
 
-    open class DummyEngineView(context: Context?) : FrameLayout(context), EngineView {
+    open class DummyEngineView(context: Context) : FrameLayout(context), EngineView {
         override fun captureThumbnail(onFinish: (Bitmap?) -> Unit) = Unit
         override fun render(session: EngineSession) {}
     }

components/concept/engine/src/test/java/mozilla/components/concept/engine/request/RequestInterceptorTest.kt

@@ -19,15 +19,10 @@ class RequestInterceptorTest {
         val urlResponse = InterceptionResponse.Url("https://mozilla.org")
         val contentReponse = InterceptionResponse.Content("data")
 
-        var url: String = when (urlResponse) {
-            is InterceptionResponse.Url -> urlResponse.url
-            else -> ""
-        }
-        var content: Triple<String, String, String> = when (contentReponse) {
-            is InterceptionResponse.Content ->
-                Triple(contentReponse.data, contentReponse.encoding, contentReponse.mimeType)
-            else -> Triple("", "", "")
-        }
+        val url: String = urlResponse.url
+
+        val content: Triple<String, String, String> =
+            Triple(contentReponse.data, contentReponse.encoding, contentReponse.mimeType)
 
         assertEquals("https://mozilla.org", url)
         assertEquals(Triple("data", "UTF-8", "text/html"), content)