Fix number parsing in range (-1, 0)

:Release Notes:
Fix parsing negative fractional numbers with zero whole part.

:Detailed Notes:
Proprietary number parsing algorithm is buggy. Whole part was used to
carry sign to the fractional part. If the whole part is zero, the
information about the sign was lost.

:Testing Performed:
Unit tests.

:QA Notes:

:Issues Addressed:
[BHV-12121] SmartShare application doesn't have support for -1/2x rewind

Open-webOS-DCO-1.0-Signed-off-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>

Change-Id: I6002daa31d1132c26df4bccefa4d11072305b0ab
Reviewed-on: https://g2g.palm.com/6371
Reviewed-by: DCO Verification
Tested-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>
Reviewed-by: Andrii Zora <andrii.zora@lge.com>
Reviewed-by: Oleksii Rudenko <oleksii.rudenko@lge.com>
Reviewed-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>