Back out r29592 (-Wl,-pie) because apparently Valgrind doesn't understand

executable slide.

BUG=25372
TEST=green tree
Review URL: http://codereview.chromium.org/311001

git-svn-id: http://src.chromium.org/svn/trunk/src/build@29604 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

common.gypi

@@ -742,13 +742,6 @@
           ['_mac_bundle', {
             'xcode_settings': {'OTHER_LDFLAGS': ['-Wl,-ObjC']},
           }],
-          ['_type=="executable"', {
-            'xcode_settings': {
-              'OTHER_LDFLAGS': [
-                '-Wl,-pie',  # Position-independent executable (MH_PIE)
-              ],
-            },
-          }],
           ['_type=="executable" or _type=="shared_library"', {
             'target_conditions': [
               ['mac_real_dsym == 1', {