content_child: Explicitly depend on blink_image_resources.

content_child: Explicitly depend on blink_image_resources.

Commit a3c614c9 ("Part 4 of ??: Move blink images to their own grd/pak
files") introduced a dependency on the newly-generated blink_resources.h
header in blink_platform_impl.cc, but did not explicitly made the
content_child target depend on the target that generated it.

Other targets elsewhere work fine because they depend on one or more pak
files also generated by the grit invocation, but that is not the case
for content_child, which only uses the header that's created.

BUG=467176, 471609
TEST=ninja -C out/Release content_child [from scratch]
R=erg@chromium.org, jam@chromium.org, sky@chromium.org

Committed: https://crrev.com/9f07769a87f59dd4f70b9a481a4f594faf18c8ab
Cr-Commit-Position: refs/heads/master@{#325651}

[sky, 2015-04-17 15:31:32]

LGTM

[Raphael Kubo da Costa (rakuco), 2015-04-17 15:32:52]

The CQ bit was checked by raphael.kubo.da.costa@intel.com

[commit-bot: I haz the power, 2015-04-17 15:33:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1088513006/1

[jam, 2015-04-17 15:33:55]

lgtm

[commit-bot: I haz the power, 2015-04-17 16:35:54]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-04-17 16:41:45]

Patchset 1 (id:??) landed as
https://crrev.com/9f07769a87f59dd4f70b9a481a4f594faf18c8ab
Cr-Commit-Position: refs/heads/master@{#325651}