Code: void PresentationConnectionProxy::DidChangeState(
    content::PresentationConnectionState state) {
  if (state == content::PRESENTATION_CONNECTION_STATE_CONNECTED) {
     source_connection_->didChangeState(
         blink::WebPresentationConnectionState::Connected);
   } else if (state == content::PRESENTATION_CONNECTION_STATE_CLOSED) {
    source_connection_->didChangeState(
        blink::WebPresentationConnectionState::Closed);
   } else {
     NOTREACHED();
   }
 }

Vulnerability Type: DoS 
CWE ID: 
Summary: Multiple unspecified vulnerabilities in Google Chrome before 40.0.2214.111 on Windows, OS X, and Linux and before 40.0.2214.109 on Android allow attackers to cause a denial of service or possibly have other impact via unknown vectors.
Commit Message: [Presentation API] Add layout test for connection.close() and fix test failures

Add layout test.

1-UA connection.close() hits NOTREACHED() in PresentationConnection::didChangeState(). Use PresentationConnection::didClose() instead.

BUG=697719

Review-Url: https://codereview.chromium.org/2730123003
Cr-Commit-Position: refs/heads/master@{#455225}