Clean up LappedTransform and Blocker.

  - Remove unnecessary window member from lapped_transform.
  - Add comment indicated that Blocker does not take ownership of
    the window passed to its constructor.
  - Streamline LappedTransform constructor so members can be const.

Also use a range-based for loop in audio_processing_impl.cc for clarity.

R=aluebs@webrtc.org, andrew@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/41229004

Cr-Commit-Position: refs/heads/master@{#8708}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8708 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_processing/audio_processing_impl.cc b/webrtc/modules/audio_processing/audio_processing_impl.cc
index 200aa8b..9692c8c 100644
--- a/webrtc/modules/audio_processing/audio_processing_impl.cc
+++ b/webrtc/modules/audio_processing/audio_processing_impl.cc
@@ -278,9 +278,8 @@
                                        fwd_out_format_.samples_per_channel()));
 
   // Initialize all components.
-  std::list<ProcessingComponent*>::iterator it;
-  for (it = component_list_.begin(); it != component_list_.end(); ++it) {
-    int err = (*it)->Initialize();
+  for (auto item : component_list_) {
+    int err = item->Initialize();
     if (err != kNoError) {
       return err;
     }
@@ -412,9 +411,9 @@
 
 void AudioProcessingImpl::SetExtraOptions(const Config& config) {
   CriticalSectionScoped crit_scoped(crit_);
-  std::list<ProcessingComponent*>::iterator it;
-  for (it = component_list_.begin(); it != component_list_.end(); ++it)
-    (*it)->SetExtraOptions(config);
+  for (auto item : component_list_) {
+    item->SetExtraOptions(config);
+  }
 
   if (transient_suppressor_enabled_ != config.Get<ExperimentalNs>().enabled) {
     transient_suppressor_enabled_ = config.Get<ExperimentalNs>().enabled;
@@ -915,9 +914,8 @@
   }
 
   int enabled_count = 0;
-  std::list<ProcessingComponent*>::const_iterator it;
-  for (it = component_list_.begin(); it != component_list_.end(); it++) {
-    if ((*it)->is_component_enabled()) {
+  for (auto item : component_list_) {
+    if (item->is_component_enabled()) {
       enabled_count++;
     }
   }