Make it possible to use goto_definition on "broken" imports

jedi/evaluate/imports.py

@@ -239,11 +239,6 @@ class Importer(object):
         self._evaluator = evaluator
         self.level = level
         self.module_context = module_context
-        try:
-            self.file_path = module_context.py__file__()
-        except AttributeError:
-            # Can be None for certain compiled modules like 'builtins'.
-            self.file_path = None
 
         self._fixed_sys_path = None
         self._inference_possible = True
@@ -316,10 +311,16 @@ class Importer(object):
             + sys_path.check_sys_path_modifications(self.module_context)
         )
 
-        if self.import_path and self.file_path is not None \
-                and self._evaluator.environment.version_info.major == 2:
-            # Python2 uses an old strange way of importing relative imports.
-            sys_path_mod.append(force_unicode(os.path.dirname(self.file_path)))
+        if self.import_path:
+            try:
+                file_path = self.module_context.py__file__()
+            except AttributeError:
+                # Can be None for certain compiled modules like 'builtins'.
+                file_path = None
+            else:
+                if self._evaluator.environment.version_info.major == 2:
+                    # Python2 uses an old strange way of importing relative imports.
+                    sys_path_mod.append(force_unicode(os.path.dirname(file_path)))
 
         return sys_path_mod