[inspector] include test/inspector.gyp only when inspector is enabled

gypfiles/all.gyp

Index: gypfiles/all.gyp
diff --git a/gypfiles/all.gyp b/gypfiles/all.gyp
index 6b4ef82d6906c15b6a09b0f0180255c48fc7f3b0..931cc4226c6084ad96222ab66054d31a38946227 100644
--- a/gypfiles/all.gyp
+++ b/gypfiles/all.gyp
@@ -25,6 +25,11 @@
             '../test/unittests/unittests.gyp:*',
           ],
         }],
+        ['v8_enable_inspector==1', {
+          'dependencies': [
+            '../test/inspector/inspector.gyp:*',
+          ],
+        }],
         ['test_isolation_mode != "noop"', {
           'dependencies': [
             '../test/bot_default.gyp:*',