Fixes to make shared build work for app (chrome) target on linux.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 1d81fb24e17fa6d32c11837dbe6e4872d9092376..fafd7b90af3cc1fec641879c887f07dee36bc453 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -215,10 +215,17 @@
           # TODO(sgk): investigate handling this not by re-ordering the
           # flags this way, but by adding a hook to use the SCons
           # ParseFlags() option on the output from pkg-config.
-          'LINKCOM': [['$FLOCK_LINK', '-o', '$TARGET', '$_LIBDIRFLAGS', '$LINKFLAGS', '$SOURCES', '-Wl,--start-group', '$_LIBFLAGS', '-Wl,--end-group']],
           'SHLINKCOM': [['$FLOCK_SHLINK', '-o', '$TARGET', '$_LIBDIRFLAGS', '$SHLINKFLAGS', '$SOURCES', '-Wl,--start-group', '$_LIBFLAGS', '-Wl,--end-group']],
           'LDMODULECOM': [['$FLOCK_LDMODULE', '-o', '$TARGET', '$_LIBDIRFLAGS', '$LDMODULEFLAGS', '$SOURCES', '-Wl,--start-group', '$_LIBFLAGS', '-Wl,--end-group']],
           'IMPLICIT_COMMAND_DEPENDENCIES': 0,
+          # rpath is only used when doing a shared build
+          'conditions': [
+            [ 'library=="shared_library"', {
+              'LINKCOM': [['$FLOCK_LINK', '-o', '$TARGET', '$_LIBDIRFLAGS', '$LINKFLAGS', '$SOURCES', '-Wl,-rpath', '-Wl,$LIB_DIR', '-Wl,--start-group', '$_LIBFLAGS', '-Wl,--end-group']],
+            }, {  # else: library!="shared_library"
+              'LINKCOM': [['$FLOCK_LINK', '-o', '$TARGET', '$_LIBDIRFLAGS', '$LINKFLAGS', '$SOURCES', '-Wl,--start-group', '$_LIBFLAGS', '-Wl,--end-group']],
+            }],
+          ],
         },
         'scons_import_variables': [
           'CC',