Add missing instruction_map.cc in sdch/SConscript.

This fixes the SHARED=1 build on Linux. sdch/SConscript last changed in r8644/issue 18717.
Review URL: http://codereview.chromium.org/18816

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@8675 0039d316-1c4b-4281-b951-d872f2087c98

sdch/SConscript

@@ -30,6 +30,7 @@ input_files = ChromeFileList([
     'open-vcdiff/src/decodetable.h',
     'open-vcdiff/src/encodetable.h',
     'open-vcdiff/src/headerparser.h',
+    'open-vcdiff/src/instruction_map.h',
     'open-vcdiff/src/logging.h',
     'open-vcdiff/src/google/output_string.h',
     'open-vcdiff/src/rolling_hash.h',
@@ -50,6 +51,7 @@ input_files = ChromeFileList([
     'open-vcdiff/src/decodetable.cc',
     'open-vcdiff/src/encodetable.cc',
     'open-vcdiff/src/headerparser.cc',
+    'open-vcdiff/src/instruction_map.cc',
     'open-vcdiff/src/logging.cc',
     'open-vcdiff/src/varint_bigendian.cc',
     'open-vcdiff/src/vcdecoder.cc',