fix: contexts serializer avoids reflection and fixes desugaring issue (#478)

Author: marandaneto

sentry-android-core/src/main/java/io/sentry/android/core/AndroidSerializer.java

@@ -4,6 +4,7 @@
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import io.sentry.android.core.adapters.ContextsDeserializerAdapter;
+import io.sentry.android.core.adapters.ContextsSerializerAdapter;
 import io.sentry.android.core.adapters.DateDeserializerAdapter;
 import io.sentry.android.core.adapters.DateSerializerAdapter;
 import io.sentry.android.core.adapters.OrientationDeserializerAdapter;
@@ -96,6 +97,7 @@ Device.DeviceOrientation.class, new OrientationDeserializerAdapter(logger))
         .registerTypeAdapter(SentryLevel.class, new SentryLevelSerializerAdapter(logger))
         .registerTypeAdapter(SentryLevel.class, new SentryLevelDeserializerAdapter(logger))
         .registerTypeAdapter(Contexts.class, new ContextsDeserializerAdapter(logger))
+        .registerTypeAdapter(Contexts.class, new ContextsSerializerAdapter(logger))
         .registerTypeAdapterFactory(UnknownPropertiesTypeAdapterFactory.get())
         .registerTypeAdapter(SentryEnvelopeHeader.class, new SentryEnvelopeHeaderAdapter())
         .registerTypeAdapter(SentryEnvelopeItemHeader.class, new SentryEnvelopeItemHeaderAdapter())

sentry-android-core/src/main/java/io/sentry/android/core/adapters/ContextsSerializerAdapter.java

@@ -0,0 +1,44 @@
+package io.sentry.android.core.adapters;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+import io.sentry.core.ILogger;
+import io.sentry.core.SentryLevel;
+import io.sentry.core.protocol.Contexts;
+import java.lang.reflect.Type;
+import java.util.Map;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+@ApiStatus.Internal
+public final class ContextsSerializerAdapter implements JsonSerializer<Contexts> {
+
+  private final @NotNull ILogger logger;
+
+  public ContextsSerializerAdapter(@NotNull final ILogger logger) {
+    this.logger = logger;
+  }
+
+  @Override
+  public JsonElement serialize(Contexts src, Type typeOfSrc, JsonSerializationContext context) {
+    if (src == null) {
+      return null;
+    }
+
+    final JsonObject object = new JsonObject();
+    for (final Map.Entry<String, Object> entry : src.entrySet()) {
+      try {
+        final JsonElement element = context.serialize(entry.getValue(), Object.class);
+        if (element != null) {
+          object.add(entry.getKey(), element);
+        }
+      } catch (JsonParseException e) {
+        logger.log(SentryLevel.ERROR, "%s context key isn't serializable.");
+      }
+    }
+    return object;
+  }
+}