Changing webmdec to use libwebm

Changing webmdec to use libwebm for WebM file parsing.

Change-Id: I2a57a7b44dbed05eaa04409e1e75e6fc03b30fbc
Add tests for simple_encoder.

Change-Id: Ia8d1ddc856aa3d350522dd8dd13abc0bf40612ee
Removing unused vp9_variance_halfpixvar*() functions.

Change-Id: I99695564a3aa9bc8c79ac0a551d257e2ff3ad3c3
scale_and_extend_frame{,_nonnormative}() cleanup.

Change-Id: Ie99fd7af436ab2f6b3ef0c3f1a652fb26116d861
Cleaning up vp9_full_search_sadx8() function.

Change-Id: I61f977a7d0b177881bd5c1a7179fa5f8f089e9a6
Removing old unused vp9_tapify.py.

Change-Id: I7d66987fd04a3f98c140fc5f99ed0e9bc01f61d0
Removing WRITE_RECON_BUFFER related code.

That code is not used, we could easily return it back using vpx_img_write()
function.

Change-Id: Id107875c6feab6ad245a518f6b437b6ed4b1246d
Merge "Changing webmdec to use libwebm"
Save NEON registers in VP8 NEON functions

The recent compiler can generate optimized code that uses NEON registers
for various operations besides floating-point operations. Therefore,
only saving callee-saved registers d8 - d15 at the beginning of the
encoder/decoder is not enough anymore. This patch added register saving
code in VP8 NEON functions that use those registers.

Change-Id: Ie9e44f5188cf410990c8aaaac68faceee9dffd31
Merge "Add tests for simple_encoder."
tools_common.sh: Add a pseudo include guard.

Change-Id: Iac931dee8fa428a2182d20e48ee515d7c77885c0
Add tests for the decode_with_drops example.

Change-Id: I99e120f934613fb7cc0ef4b4bba0c8caaecf18d2
Add script for running all example tests.

Change-Id: I1e3d0689554c9b64c035ec0394f052507f7ac2a3
Merge "Add tests for the decode_with_drops example."
Merge "Add script for running all example tests."
Adding search_site_config struct.

Change-Id: I2ad333553e673dbabcdc0f0366aea311e90849bf
Merge "Save NEON registers in VP8 NEON functions"
Merge "Removing WRITE_RECON_BUFFER related code."
Merge "Removing old unused vp9_tapify.py."
Merge "Removing unused vp9_variance_halfpixvar*() functions."