Revert of cc: Fix size_t to int truncations in layers/ output/ playback/ quads/

cc/layers/layer.cc

Index: cc/layers/layer.cc
diff --git a/cc/layers/layer.cc b/cc/layers/layer.cc
index 126b3dcf9f841bcf606e0b9e26912af3ebf2aab5..d795670192770cf273875a4bf29e67db9a660aa0 100644
--- a/cc/layers/layer.cc
+++ b/cc/layers/layer.cc
@@ -337,20 +337,26 @@
   if (reference == new_layer.get())
     return;
 
-  // Find the index of |reference| in |children_|.
-  auto reference_it =
-      std::find_if(children_.begin(), children_.end(),
-                   [reference](const scoped_refptr<Layer>& layer) {
-                     return layer.get() == reference;
-                   });
-  DCHECK(reference_it != children_.end());
-  size_t reference_index = reference_it - children_.begin();
+  int reference_index = IndexOfChild(reference);
+  if (reference_index == -1) {
+    NOTREACHED();
+    return;
+  }
+
   reference->RemoveFromParent();
 
   if (new_layer.get()) {
     new_layer->RemoveFromParent();
     InsertChild(new_layer, reference_index);
   }
+}
+
+int Layer::IndexOfChild(const Layer* reference) {
+  for (size_t i = 0; i < children_.size(); ++i) {
+    if (children_[i].get() == reference)
+      return i;
+  }
+  return -1;
 }
 
 void Layer::SetBounds(const gfx::Size& size) {
@@ -410,7 +416,7 @@
 void Layer::RequestCopyOfOutput(
     scoped_ptr<CopyOutputRequest> request) {
   DCHECK(IsPropertyChangeAllowed());
-  bool had_no_copy_requests = copy_requests_.empty();
+  int size = copy_requests_.size();
   if (void* source = request->source()) {
     auto it = std::find_if(
         copy_requests_.begin(), copy_requests_.end(),
@@ -421,7 +427,7 @@
   if (request->IsEmpty())
     return;
   copy_requests_.push_back(request.Pass());
-  if (had_no_copy_requests) {
+  if (size == 0) {
     bool copy_request_added = true;
     UpdateNumCopyRequestsForSubtree(copy_request_added);
   }
@@ -1268,7 +1274,7 @@
   layer->SetScrollCompensationAdjustment(ScrollCompensationAdjustment());
 
   // Wrap the copy_requests_ in a PostTask to the main thread.
-  bool had_copy_requests = !copy_requests_.empty();
+  int size = copy_requests_.size();
   ScopedPtrVector<CopyOutputRequest> main_thread_copy_requests;
   for (ScopedPtrVector<CopyOutputRequest>::iterator it = copy_requests_.begin();
        it != copy_requests_.end();
@@ -1287,7 +1293,7 @@
   }
   if (!copy_requests_.empty() && layer_tree_host_)
     layer_tree_host_->property_trees()->needs_rebuild = true;
-  if (had_copy_requests)
+  if (size != 0)
     UpdateNumCopyRequestsForSubtree(false);
   copy_requests_.clear();
   layer->PassCopyRequests(&main_thread_copy_requests);