Cleanup: Move kAboutScheme constant into content namespace.

android_webview/renderer/aw_content_renderer_client.cc

Index: android_webview/renderer/aw_content_renderer_client.cc
diff --git a/android_webview/renderer/aw_content_renderer_client.cc b/android_webview/renderer/aw_content_renderer_client.cc
index 7001aff2d82f4c2b29e7611b1ab26ca4ea5938ce..f6d4c7e59931debfbd960e464dc5e8bc89e131fc 100644
--- a/android_webview/renderer/aw_content_renderer_client.cc
+++ b/android_webview/renderer/aw_content_renderer_client.cc
@@ -97,7 +97,7 @@ bool AwContentRendererClient::HandleNavigation(
   // So we filter out non-top about:blank navigations here.
   if (frame->parent() && (gurl.SchemeIs(content::kHttpScheme) ||
                           gurl.SchemeIs(content::kHttpsScheme) ||
-                          gurl.SchemeIs(chrome::kAboutScheme)))
+                          gurl.SchemeIs(content::kAboutScheme)))
     return false;
 
   // use NavigationInterception throttle to handle the call as that can