NaCl: Remove reliance on "init_done" SRPC call in the non-PNaCl case

NaCl: Remove reliance on "init_done" SRPC call in the non-PNaCl case

We can remove Plugin::NexeFileDidOpenContinuation(), which gets called
via the "init_done" SRPC call (which calls
StartupInitializationComplete() in plugin/service_runtime.cc).

Its work gets done by the newer
ManifestServiceProxy::StartupInitializationComplete() in
components/nacl/renderer/ppb_nacl_private_impl.cc, which gets called
via Chrome IPC (by the "PpapiHostMsg_StartupInitializationComplete"
message).

ppapi_dispatcher.cc: In order to keep the error handling tests in
NaClBrowserTestNewlib.Bad passing, send the
StartupInitializationComplete message earlier, before we call
PPP_InitializeModule().  This ensures that crashes in
PPP_InitializeModule() are reported properly.

Note that PNaCl still relies on "init_done" for now.

BUG=428030
BUG=https://code.google.com/p/nativeclient/issues/detail?id=3864

Committed: https://crrev.com/4c03d4d0964b0b69f5741aac6c78557b415617e1
Cr-Commit-Position: refs/heads/master@{#311298}

[Mark Seaborn, 2015-01-13 16:27:38]

mseaborn@chromium.org changed reviewers:
+ teravest@chromium.org

[teravest, 2015-01-13 17:47:26]

lgtm

[Mark Seaborn, 2015-01-13 17:53:22]

The CQ bit was checked by mseaborn@chromium.org

[commit-bot: I haz the power, 2015-01-13 17:53:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/849523002/60001

[commit-bot: I haz the power, 2015-01-13 18:50:42]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2015-01-13 18:51:32]

Patchset 4 (id:??) landed as
https://crrev.com/4c03d4d0964b0b69f5741aac6c78557b415617e1
Cr-Commit-Position: refs/heads/master@{#311298}

[Mark Seaborn, 2015-01-14 06:16:12]

A revert of this CL (patchset #4 id:60001) has been created in
https://codereview.chromium.org/793723006/ by mseaborn@chromium.org.

The reason for reverting is: Reverting this change because it appears to cause
NaClBrowserTestNewlib.Bad to become flaky.

BUG=448596.