Do not check ProxyInfo if the the DRP config is not valid

Do not check ProxyInfo if the the DRP config is not valid

A previous CL (https://codereview.chromium.org/1702253002)
made a change and called result->proxy_server() without
checking if DRP config is valid. This caused Chrome
to crash because if config is not valid, calling result-
>proxy_server() may cause crashes (because there may not be
any proxy server in result).

This CL reverts back to behavior before that CL. Before
result->proxy_server() is called, it is ensured that the
DRP config must be valid.

BUG=591356
Review URL: https://codereview.chromium.org/1756323002

Cr-Commit-Position: refs/heads/master@{#379048}
(cherry picked from commit 50eb58711b04bd731486974488e46546bf45b0bb)

Committed: https://chromium.googlesource.com/chromium/src/+/af925bedc19ae2c7a7a2b065baae730edc6e3143

[tbansal1, 2016-03-07 23:08:42]

Description was changed from

==========
Do not check ProxyInfo if the the DRP config is not valid

A previous CL (https://codereview.chromium.org/1702253002)
made a change and called result->proxy_server() without
checking if DRP config is valid. This caused Chrome
to crash because if config is not valid, calling result-
>proxy_server() may cause crashes (because there may not be
any proxy server in result).

This CL reverts back to behavior before that CL. Before
result->proxy_server() is called, it is ensured that the
DRP config must be valid.

BUG=591356

Review URL: https://codereview.chromium.org/1756323002

Cr-Commit-Position: refs/heads/master@{#379048}
(cherry picked from commit 50eb58711b04bd731486974488e46546bf45b0bb)
==========

to

==========
Do not check ProxyInfo if the the DRP config is not valid

A previous CL (https://codereview.chromium.org/1702253002)
made a change and called result->proxy_server() without
checking if DRP config is valid. This caused Chrome
to crash because if config is not valid, calling result-
>proxy_server() may cause crashes (because there may not be
any proxy server in result).

This CL reverts back to behavior before that CL. Before
result->proxy_server() is called, it is ensured that the
DRP config must be valid.

BUG=591356

Review URL: https://codereview.chromium.org/1756323002

Cr-Commit-Position: refs/heads/master@{#379048}
(cherry picked from commit 50eb58711b04bd731486974488e46546bf45b0bb)

Committed:
https://chromium.googlesource.com/chromium/src/+/af925bedc19ae2c7a7a2b065baae...
==========

[tbansal1, 2016-03-07 23:08:43]

Committed patchset #1 (id:1) manually as
af925bedc19ae2c7a7a2b065baae730edc6e3143.