[NaCl SDK] nacl_io: Remove unneeded glibc syscall entry points.

[NaCl SDK] nacl_io: Remove unneeded glibc syscall entry points.

These can now be intercepted within glibc so there
is no need to implement them directly.  mkdir/mkdir
were also be intercepted at this level under newlib
unnecessarily.

It seems that truncate.c is still needed but I've
got a fix for that in glibc:
https://codereview.chromium.org/439003002/

BUG= https://code.google.com/p/nativeclient/issues/detail?id=3709
R=binji@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=287745

[Sam Clegg, 2014-08-05 17:31:00]

ptal

[binji, 2014-08-05 18:53:10]

lgtm

https://codereview.chromium.org/433193002/diff/180001/native_client_sdk/src/l...
File native_client_sdk/src/libraries/gtest/library.dsc (left):

https://codereview.chromium.org/433193002/diff/180001/native_client_sdk/src/l...
native_client_sdk/src/libraries/gtest/library.dsc:22: 'nacl_gtest_dummy_sys.cc',
OK, but this means we can't use gtest independent from nacl_io. Probably that is
OK, but we should make a note of it, I think.

[Sam Clegg, 2014-08-06 09:39:13]

On 2014/08/05 18:53:10, binji wrote:
> lgtm
> 
>
https://codereview.chromium.org/433193002/diff/180001/native_client_sdk/src/l...
> File native_client_sdk/src/libraries/gtest/library.dsc (left):
> 
>
https://codereview.chromium.org/433193002/diff/180001/native_client_sdk/src/l...
> native_client_sdk/src/libraries/gtest/library.dsc:22:
'nacl_gtest_dummy_sys.cc',
> OK, but this means we can't use gtest independent from nacl_io. Probably that
is
> OK, but we should make a note of it, I think.

Hmm, yes you are right.  If getcwd() returns ENOSYS gtest will assert on
startup.  I hadn't thought of the non-nacl-io case.
I think this is the correct way to go though.   Anyone who wants to use gtest
without nacl_io can implement a trivial getcwd().
Where should we note this?

[Sam Clegg, 2014-08-06 09:41:59]

Committed patchset #10 manually as 287745 (presubmit successful).