Address some build warnings and cleanup (#1412)

(cherry picked from commit a1c60897916f418726107fec80ad79b2a4b8d500)

core/common/build.gradle.kts

@@ -7,10 +7,11 @@ plugins {
 
 android {
     namespace = "eu.kanade.tachiyomi.core.common"
+}
 
-    kotlinOptions {
-        freeCompilerArgs += listOf(
-            "-Xcontext-receivers",
+kotlin {
+    compilerOptions {
+        freeCompilerArgs.addAll(
             "-opt-in=kotlinx.coroutines.ExperimentalCoroutinesApi",
             "-opt-in=kotlinx.serialization.ExperimentalSerializationApi",
         )

core/common/src/main/kotlin/eu/kanade/tachiyomi/util/system/WebViewUtil.kt

@@ -73,7 +73,6 @@ fun WebView.setDefaultSettings() {
     with(settings) {
         javaScriptEnabled = true
         domStorageEnabled = true
-        databaseEnabled = true
         useWideViewPort = true
         loadWithOverviewMode = true
         cacheMode = WebSettings.LOAD_DEFAULT