Add an option ProxyService::Create() to disable use of proxy auto-config....

Add an option ProxyService::Create() to disable use of proxy auto-config.
BUG=40797
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=62487

[eroman, 2010-10-11 20:09:28]

http://codereview.chromium.org/3646004/diff/1/9
File webkit/tools/test_shell/test_shell_request_context.cc (right):

http://codereview.chromium.org/3646004/diff/1/9#newcode67
webkit/tools/test_shell/test_shell_request_context.cc:67:
net::ProxyService::PROXY_RESOLVER_SYSTEM, 0, NULL, NULL, NULL);
After this change, you could easily change the policy in TestShell by changing
this to PROXY_RESOLVER_NONE.

[eroman, 2010-10-11 23:35:16]

Modified the CL to use separate function names instead of the enum.

[Marshall, 2010-10-12 13:51:34]

On Windows 7 the "Automatically detect settings" checkbox under "LAN settings"
defaults to checked. Does it make sense to support a mode on Windows where proxy
auto-detection (WINHTTP_CURRENT_USER_IE_PROXY_CONFIG.fAutoDetect) is ignored but
manually configured proxy settings (the rest of the
WINHTTP_CURRENT_USER_IE_PROXY_CONFIG structure) are still respected? I'm not
sure how common it is to manually configure proxy settings on individual Windows
computers vs. using the auto-detect feature.

[eroman, 2010-10-13 01:13:24]

I think we should keep things simple and either support proxy-autoconfig, or not
support it.

(autodetect is mostly just a fancy way of specifying the PAC URL
"http://wpad/wpad.dat")

[Marshall, 2010-10-13 13:24:15]

OK, LGTM