Apply suggestions from TG3 discussion

Author: dminor

spec.emu

@@ -15,16 +15,21 @@ markEffects: true
   <p></p>
 </emu-intro>
 
-<emu-clause id="sec-agents">
-  <h1>Agents</h1>
-
-  <emu-table id="table-agent-record" caption="Agent Record Fields">
+<emu-clause id="sec-code-realms">
+  <h1>Realms</h1>
+  <emu-table id="table-realm-record-fields" caption="Realm Record Fields" oldids="table-21">
     <table>
       <thead>
         <tr>
-          <th>Field Name</th>
-          <th>Value</th>
-          <th>Meaning</th>
+          <th>
+            Field Name
+          </th>
+          <th>
+            Value
+          </th>
+          <th>
+            Meaning
+          </th>
         </tr>
       </thead>
       <tr>
@@ -34,14 +39,6 @@ markEffects: true
       </tr>
     </table>
   </emu-table>
-
-  <p>Once the values of [[Signifier]], [[IsLockFree1]], [[IsLockFree2]], and [[ErrorCaptureStackTraceStrategy]] have been observed by any agent in the agent cluster they cannot change.</p>
-</emu-clause>
-
-<emu-clause id="sec-agent-clusters">
-  <h1>Agent Clusters</h1>
-
-  <p>All agents within a cluster must have the same value for the [[ErrorCaptureStackTraceStrategy]] field in their respective Agent Records.</p>
 </emu-clause>
 
 <emu-clause id="sec-fundamental-objects" number="20">
@@ -54,29 +51,28 @@ markEffects: true
       <h1>Properties of the Error Constructor</h1>
 
       <emu-clause id="sec-error.capturestacktrace">
-        <h1>Error.captureStackTrace ( _error_ [ , _constructor_ ] )</h1>
+        <h1>Error.captureStackTrace ( _O_ [ , _limit_ ] )</h1>
         <emu-alg>
-          1. If _error_ is not an Object, throw a *TypeError* exception.
-          1. If IsCallable(_constructor_) is *true*, then
+          1. If _O_ is not an Object, throw a *TypeError* exception.
+          1. If IsCallable(_limit_) is *true*, then
             1. Let _string_ be an implementation-defined string that represents the current stack trace, with all stack
-               frames above the topmost call to _constructor_, including that call, omitted from the stack trace.
+               frames above the topmost call to _limit_, including that call, omitted from the stack trace.
             1. NOTE: This can be used to hide implementation details on the stack trace that aren't useful to user.
           1. Else,
             1. Let _string_ be an implementation-defined string that represents the current stack trace.
-          1. Let _strategy_ be the value of the [[ErrorCaptureStackTraceStrategy]] field of the surrounding agent's Agent Record.
+          1. Let _strategy_ be the value of the [[ErrorCaptureStackTraceStrategy]] field of the current Realm Record.
           1. If _strategy_ is ~data-property~, then
-            1. Perform ? SetterThatIgnoresPrototypeProperties(_error_, OrdinaryObjectCreate(*null*), *"stack"*, _string_)..
+            1. Perform ? DefinePropertyOrThrow(_O_, *"stack"*, PropertyDescriptor { [[Value]]: _string_, [[Writable]]: true, [[Enumerable]]: true, [[Configurable]]: true }).
           1. Else,
             1. Assert: _strategy_ is ~accessor~.
-            1. If ? IsExtensible(_error_) is *false*, throw a *TypeError* exception.
             1. Let _getterClosure_ be a new Abstract Closure with no parameters that captures _string_ and performs the following steps when called:
               1. Return NormalCompletion(_string_).
             1. Let _getter_ be CreateBuiltinFunction(_getterClosure_, 0, "", « »).
-            1. Let _setterClosure_ be a new Abstract Closure with parameters (_value_) that captures _error_ and performs the following steps when called:
-              1. Perform ? SetterThatIgnoresPrototypeProperties(_error_, *null*, *"stack"*, _value_).
+            1. Let _setterClosure_ be a new Abstract Closure with parameters (_value_) that captures _O_ and performs the following steps when called:
+              1. Perform ? DefinePropertyOrThrow(_O_, *"stack"*, PropertyDescriptor { [[Value]]: _value_, [[Writable]]: true, [[Enumerable]]: true, [[Configurable]]: true }).
               1. Return NormalCompletion(*undefined*).
             1. Let _setter_ be CreateBuiltinFunction(_setterClosure_, 1, "", « »).
-            1. Perform ! OrdinaryDefineOwnProperty(_error_, *"stack"*, PropertyDescriptor { [[Get]]: _getter_, [[Set]]: _setter_, [[Enumerable]]: false, [[Configurable]]: true }).
+            1. Perform ? DefinePropertyOrThrow(_O_, *"stack"*, PropertyDescriptor { [[Get]]: _getter_, [[Set]]: _setter_, [[Enumerable]]: false, [[Configurable]]: true }).
           1. Return *undefined*.
         </emu-alg>
       </emu-clause>