Fix various typos in ART's comments and string literals.

Change-Id: I85d628055b1a61647a77fef730c9631c234e22a2
diff --git a/runtime/gc/collector/mark_compact.cc b/runtime/gc/collector/mark_compact.cc
index ce6467a..7727b2d 100644
--- a/runtime/gc/collector/mark_compact.cc
+++ b/runtime/gc/collector/mark_compact.cc
@@ -180,7 +180,7 @@
   t.NewTiming("ProcessCards");
   // Process dirty cards and add dirty cards to mod-union tables.
   heap_->ProcessCards(GetTimings(), false, false, true);
-  // Clear the whole card table since we can not Get any additional dirty cards during the
+  // Clear the whole card table since we cannot get any additional dirty cards during the
   // paused GC. This saves memory but only works for pause the world collectors.
   t.NewTiming("ClearCardTable");
   heap_->GetCardTable()->ClearCardTable();