minor changes left out of http://crrev.com/873543002

src/pdf/SkPDFCanon.cpp

Index: src/pdf/SkPDFCanon.cpp
diff --git a/src/pdf/SkPDFCanon.cpp b/src/pdf/SkPDFCanon.cpp
index bea1400bd64ca5de40a59d78fe38dc6ea061211f..6b52018ce41e81ae08c6b8688f43b6846def3d19 100644
--- a/src/pdf/SkPDFCanon.cpp
+++ b/src/pdf/SkPDFCanon.cpp
@@ -39,7 +39,6 @@ static void assert_mutex_held(const SkPDFCanon* canon, SkBaseMutex& mutex) {
 
 template <class T> T* assert_ptr(T* p) { SkASSERT(p); return p; }
 
-// TODO(halcanary):  add this method to SkTDArray.
 template <typename T>
 bool remove_item(SkTDArray<T>* array, const T& elem) {
     int i = array->find(elem);