[SSL] Componentize SSLErrorHandler unittest

Follows the componentization of the production class. One note is that
there are multiple independent test classes in the unittest file that
all construct TestSSLErrorHandler instances. As the manual construction
of a CaptivePortalService instance is somewhat cumbersome, we did it
only in the tests that actually need it; in the other tests we simply
pass nullptr. This is analogous to the how the tests are handling the
NetworkTimeTracker parameter of TestSSLErrorHandler. Finally, the test
is augmented to account for the fact that on Chromecast, where the test
now runs as part of components_unittests, captive portal detection is
not enabled.

Bug: 1030692
Change-Id: If9292ebbf26437ef85f42f248468325f6d1795f5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2030524
Commit-Queue: Colin Blundell <[email protected]>
Reviewed-by: Carlos IL <[email protected]>
Cr-Commit-Position: refs/heads/master@{#737293}
4 files changed