[WebView] Fix GN builds that use "use_webview_internal_framework".

android_webview/tools/BUILD.gn

Index: android_webview/tools/BUILD.gn
diff --git a/android_webview/tools/BUILD.gn b/android_webview/tools/BUILD.gn
index 6d542cbe3faf56324688ee8446a98ca3f729a108..f10f66e455390323011d2b05d13dcfc0e10f9e38 100644
--- a/android_webview/tools/BUILD.gn
+++ b/android_webview/tools/BUILD.gn
@@ -45,7 +45,6 @@ instrumentation_test_apk("system_webview_shell_page_cycler_apk") {
     "//content/public/test/android:content_java_test_support",
     "//testing/android/reporter:reporter_java",
   ]
-  additional_apks = [ "//android_webview:system_webview_apk" ]
 }
 
 # GYP: //android_webview/android_webview_shell.gypi:system_webview_shell_layout_test_apk
@@ -60,5 +59,4 @@ instrumentation_test_apk("system_webview_shell_layout_test_apk") {
     "//base:base_java_test_support",
     "//testing/android/reporter:reporter_java",
   ]
-  additional_apks = [ "//android_webview:system_webview_apk" ]
 }