This is the first patch to enable row major matrix suppot in series. This patch
ensures that we can get correct location when we load/store data from matrix.
Currently, only scalar data load/store works well.

mat2x3 data
The location of data[x][y] will be:
data.offset + x * scalarStride + y * matrixStride  //row_major
data.offset + x * matrixStride + y * scalarStride  //column_major

Bug: angleproject:1951
Change-Id: I5bd7bad7d293219ba610f18eeafc56e70e36de43
Reviewed-on: https://chromium-review.googlesource.com/c/1304017Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Jiajia Qin <jiajia.qin@intel.com>