AudioBufferSourceNode.buffer can only be set once.

Source/core/frame/UseCounter.cpp

Index: Source/core/frame/UseCounter.cpp
diff --git a/Source/core/frame/UseCounter.cpp b/Source/core/frame/UseCounter.cpp
index 676ae496fe1b6a5128779707e8ca833b6f4c7b16..bc7b3c040bf260a296aa2048afb3b4ebb400e280 100644
--- a/Source/core/frame/UseCounter.cpp
+++ b/Source/core/frame/UseCounter.cpp
@@ -830,6 +830,9 @@ String UseCounter::deprecationMessage(Feature feature)
     case RangeExpand:
         return replacedBy("Range.expand()", "Selection.modify()");
 
+    case AudioBufferSourceBufferOnce:
+        return "Setting AudioBufferSourceNode.buffer more than once is deprecated and will no longer work in M45.";

[Ken Russell (switch to Gerrit), 2015/01/21 22:58:46]

Better to say "Chrome 45"? Also, feel free to pull move this up to an earlier
release like Chrome 43. Also please communicate this change as widely as
possible on public mailing lists.

[Raymond Toy, 2015/01/21 23:16:27]

Chrome 43 it is.  Will add entry to the chrome status dashboard

+
     // Features that aren't deprecated don't have a deprecation message.
     default:
         return String();