HttpsURLConnectionTest rewrite and URLConnectionTest updates

Rewrote HttpsURLConnectionTest to work with current SSLSocket
implementation which more strictly follows RI behavior.

Also made upates to URLConnectionTest related to HttpsURLConnection
- changed assertContent call connect() explictly to illustrate problem
  with https proxy case also seen by HttpsURLConnectionTest
- Rewrote testConnectTimeouts to work reliably. Before if often
  worked on WiFi but not on mobile networks where a "HTTP/1.1 501 Bad
  Gateway" would be seen causing a FileNotFoundException.
- Changed testConnectViaHttpProxyToHttpsUsingHttpProxySystemProperty
  to match expectation that https does not use the http.proxyHost
  values. Added new testConnectViaHttpProxyToHttpsUsingProxyArgWithNoProxy
  which should have the same behavior as the fixed
  testConnectViaHttpProxyToHttpsUsingHttpProxySystemProperty

git cherry-pick -e f02c695ed03e708623d9365dec26d533356ef2d0

Bug: 3184701
Change-Id: Id25f619d2437db607deaf35aeb1d5e817514b92f