--- a/python/mozbuild/mozbuild/frontend/gyp_reader.py
+++ b/python/mozbuild/mozbuild/frontend/gyp_reader.py
@@ -47,70 +47,72 @@ def encode(value):
     return value
 
 
 # Default variables gyp uses when evaluating gyp files.
 generator_default_variables = {
 }
 for dirname in [b'INTERMEDIATE_DIR', b'SHARED_INTERMEDIATE_DIR', b'PRODUCT_DIR',
                 b'LIB_DIR', b'SHARED_LIB_DIR']:
-  # Some gyp steps fail if these are empty(!).
-  generator_default_variables[dirname] = b'$' + dirname
+    # Some gyp steps fail if these are empty(!).
+    generator_default_variables[dirname] = b'$' + dirname
 
 for unused in ['RULE_INPUT_PATH', 'RULE_INPUT_ROOT', 'RULE_INPUT_NAME',
                'RULE_INPUT_DIRNAME', 'RULE_INPUT_EXT',
                'EXECUTABLE_PREFIX', 'EXECUTABLE_SUFFIX',
                'STATIC_LIB_PREFIX', 'STATIC_LIB_SUFFIX',
                'SHARED_LIB_PREFIX', 'SHARED_LIB_SUFFIX',
                'LINKER_SUPPORTS_ICF']:
-  generator_default_variables[unused] = b''
+    generator_default_variables[unused] = b''
 
 
 class GypContext(TemplateContext):
     """Specialized Context for use with data extracted from Gyp.
 
     config is the ConfigEnvironment for this context.
     relobjdir is the object directory that will be used for this context,
     relative to the topobjdir defined in the ConfigEnvironment.
     """
     def __init__(self, config, relobjdir):
         self._relobjdir = relobjdir
         TemplateContext.__init__(self, template='Gyp',
             allowed_variables=VARIABLES, config=config)
 
 
 def handle_actions(actions, context, action_overrides):
-  idir = '$INTERMEDIATE_DIR/'
-  for action in actions:
-    name = action['action_name']
-    if name not in action_overrides:
-      raise RuntimeError('GYP action %s not listed in action_overrides' % name)
-    outputs = action['outputs']
-    if len(outputs) > 1:
-      raise NotImplementedError('GYP actions with more than one output not supported: %s' % name)
-    output = outputs[0]
-    if not output.startswith(idir):
-      raise NotImplementedError('GYP actions outputting to somewhere other than <(INTERMEDIATE_DIR) not supported: %s' % output)
-    output = output[len(idir):]
-    context['GENERATED_FILES'] += [output]
-    g = context['GENERATED_FILES'][output]
-    g.script = action_overrides[name]
-    g.inputs = action['inputs']
+    idir = '$INTERMEDIATE_DIR/'
+    for action in actions:
+        name = action['action_name']
+        if name not in action_overrides:
+            raise RuntimeError('GYP action %s not listed in action_overrides' % name)
+        outputs = action['outputs']
+        if len(outputs) > 1:
+            raise NotImplementedError('GYP actions with more than one output not supported: %s' % name)
+        output = outputs[0]
+        if not output.startswith(idir):
+            raise NotImplementedError('GYP actions outputting to somewhere other than <(INTERMEDIATE_DIR) not supported: %s' % output)
+        output = output[len(idir):]
+        context['GENERATED_FILES'] += [output]
+        g = context['GENERATED_FILES'][output]
+        g.script = action_overrides[name]
+        g.inputs = action['inputs']
+
 
 def handle_copies(copies, context):
-  dist = '$PRODUCT_DIR/dist/'
-  for copy in copies:
-    dest = copy['destination']
-    if not dest.startswith(dist):
-      raise NotImplementedError('GYP copies to somewhere other than <(PRODUCT_DIR)/dist not supported: %s' % dest)
-    dest_paths = dest[len(dist):].split('/')
-    exports = context['EXPORTS']
-    while dest_paths:
-      exports = getattr(exports, dest_paths.pop(0))
-    exports += sorted(copy['files'], key=lambda x: x.lower())
+    dist = '$PRODUCT_DIR/dist/'
+    for copy in copies:
+        dest = copy['destination']
+        if not dest.startswith(dist):
+            raise NotImplementedError('GYP copies to somewhere other than <(PRODUCT_DIR)/dist not supported: %s' % dest)
+        dest_paths = dest[len(dist):].split('/')
+        exports = context['EXPORTS']
+        while dest_paths:
+            exports = getattr(exports, dest_paths.pop(0))
+        exports += sorted(copy['files'], key=lambda x: x.lower())
+
 
 def read_from_gyp(config, path, output, vars, no_chromium, no_unified, action_overrides, non_unified_sources = set()):
     """Read a gyp configuration and emits GypContexts for the backend to
     process.
 
     config is a ConfigEnvironment, path is the path to a root gyp configuration
     file, output is the base path under which the objdir for the various gyp
     dependencies will be, and vars a dict of variables to pass to the gyp