(wip) Refactor pause actions (firefox-devtools#4439)

* Update Pause Semantics

Author: jasonLaster

src/actions/ast.js

@@ -9,7 +9,6 @@ import {
   getPreview
 } from "../selectors";
 
-import { ensureParserHasSourceText } from "./sources";
 import { getMappedExpression } from "./expressions";
 import { PROMISE } from "../utils/redux/middleware/promise";
 import {
@@ -38,7 +37,7 @@ export function setSymbols(sourceId: SourceId) {
     }
 
     const source = sourceRecord.toJS();
-    if (!source.text || hasSymbols(getState(), source)) {
+    if (!source.text || source.isWasm || hasSymbols(getState(), source)) {
       return;
     }
 
@@ -60,7 +59,7 @@ export function setEmptyLines(sourceId: SourceId) {
     }
 
     const source = sourceRecord.toJS();
-    if (!source.text) {
+    if (!source.text || source.isWasm) {
       return;
     }
 
@@ -147,9 +146,6 @@ export function setPreview(
             source.toJS()
           );
 
-          const generatedSourceId = generatedLocation.sourceId;
-          await dispatch(ensureParserHasSourceText(generatedSourceId));
-
           expression = await getMappedExpression(
             { sourceMaps },
             generatedLocation,

src/actions/expressions.js

@@ -9,7 +9,6 @@ import {
 } from "../selectors";
 import { PROMISE } from "../utils/redux/middleware/promise";
 import { replaceOriginalVariableName } from "devtools-map-bindings/src/utils";
-import { ensureParserHasSourceText } from "./sources";
 import { isGeneratedId } from "devtools-source-map";
 import { wrapExpression } from "../utils/expressions";
 import * as parser from "../workers/parser";
@@ -117,9 +116,6 @@ function evaluateExpression(expression: Expression) {
       const sourceId = source.get("id");
 
       if (!isGeneratedId(sourceId)) {
-        const generatedSourceId = generatedLocation.sourceId;
-        await dispatch(ensureParserHasSourceText(generatedSourceId));
-
         input = await getMappedExpression(
           { sourceMaps },
           generatedLocation,