Add a target to produce a SyzyASan instrumented version of pdf.dll

This will be used on Clusterfuzz, and we might ship this on the Canary sometimes if the performances are reasonable.

BUG=

Review URL: https://codereview.chromium.org/321303002

git-svn-id: http://src.chromium.org/svn/trunk/src/build@276746 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

all.gyp

@@ -675,6 +675,7 @@
               'dependencies': [
                 '../chrome/chrome_syzygy.gyp:chrome_dll_syzygy',
                 '../content/content_shell_and_tests.gyp:content_shell_syzyasan',
+                '../pdf/pdf.gyp:pdf_syzyasan',
               ],
               'conditions': [
                 ['chrome_multiple_dll==1', {