Add #6939

Author: daymxn

firebase-vertexai/src/main/kotlin/com/google/firebase/vertexai/common/APIController.kt

@@ -164,7 +164,7 @@ internal constructor(
     "wss://firebasevertexai.googleapis.com/ws/google.firebase.vertexai.v1beta.LlmBidiService/BidiGenerateContent/locations/$location?key=$key"
 
   suspend fun getWebSocketSession(location: String): ClientWebSocketSession =
-    client.webSocketSession(getBidiEndpoint(location))
+    client.webSocketSession(getBidiEndpoint(location)) { applyCommonHeaders() }
 
   fun generateContentStream(
     request: GenerateContentRequest
@@ -197,6 +197,11 @@ internal constructor(
       is CountTokensRequest -> setBody<CountTokensRequest>(request)
       is GenerateImageRequest -> setBody<GenerateImageRequest>(request)
     }
+
+    applyCommonHeaders()
+  }
+
+  private fun HttpRequestBuilder.applyCommonHeaders() {
     contentType(ContentType.Application.Json)
     header("x-goog-api-key", key)
     header("x-goog-api-client", apiClient)