Start isolate outdir in build directory

build/isolate.gypi

Index: build/isolate.gypi
diff --git a/build/isolate.gypi b/build/isolate.gypi
index 0f0a163716ae5515f7ec22774fc6f512f0233705..6ddc3fef2bfd1a3748f1103fff2c9fe18d9e609d 100644
--- a/build/isolate.gypi
+++ b/build/isolate.gypi
@@ -60,16 +60,20 @@
         'python',
         '<(DEPTH)/tools/swarm_client/isolate.py',
         '<(test_isolation_mode)',
-        '--outdir', '<(test_isolation_outdir)',
         '--variable', 'PRODUCT_DIR', '<(PRODUCT_DIR)',
         '--variable', 'OS', '<(OS)',
         '--variable', 'chromeos', '<(chromeos)',
         '--result', '<@(_outputs)',
         '--isolate', '<(RULE_INPUT_PATH)',
-        # Remove once mac compiles are fixed.
-        '-v',
-        '-v',
       ],
+      'conditions': [
+        ["test_isolation_outdir!=''", {
+          'action': [
+            '--outdir', '<(PRODUCT_DIR)/<(test_isolation_outdir)',
+          ],
+        }],
+      ],
+
       'msvs_cygwin_shell': 0,
     },
   ],