Improve robustness of dependency inference

Update the patterns used to detect module dependencies to tolerate
string literals which may appear on the same line as module specifiers.
Further improve the pattern so that it does not match all
U+0022-delimited string literals and so that it does not require a
trailing semicolon.

lib/dependencies.js

@@ -26,7 +26,7 @@ function findModuleSpecifiers(source) {
   let lines = source.split(/\r?\n/g);
   return lines.reduce((accum, line) => {
     if (line.includes('.js') || line.includes('.mjs')) {
-      let parsed = /(import|import\(|from)(\s*)'(.*)'|"(.*)";/g.exec(line);
+      let parsed = /(import|import\(|from)(\s*)('(.*?)'|"(.*?)")/g.exec(line);
       if (parsed && parsed.length) {
         for (let entry of parsed) {
           if (entry &&

test/fixtures/fake-test262/test/language/module-code/import-assertion-1_FIXTURE.js

@@ -0,0 +1 @@
+export default 1;

test/fixtures/fake-test262/test/language/module-code/import-assertion-2_FIXTURE.js

@@ -0,0 +1 @@
+export default 2;

test/fixtures/fake-test262/test/language/module-code/import-assertion-dynamic.js

@@ -0,0 +1,18 @@
+/*---
+description: Dynamic import assertions
+info: |
+  This test approximates the "import assertions" syntax using code comments in
+  order to support improvements to ESHost's dependency inferrence logic while
+  still passing in runtimes which do not yet support the proposed language
+  extension.
+esid: sec-moduleevaluation
+flags: [module, async]
+---*/
+
+Promise.all([
+  import('./import-assertion-1_FIXTURE.js'),//, {'':''})
+  import("./import-assertion-2_FIXTURE.js"),//, {"":""})
+]).then(function(values) {
+  assert.sameValue(values[0].default, 1);
+  assert.sameValue(values[1].default, 2);
+}).then($DONE, $DONE);

test/fixtures/fake-test262/test/language/module-code/import-assertion-static.js

@@ -0,0 +1,18 @@
+/*---
+description: Static import assertions
+info: |
+  This test approximates the "import assertions" syntax using code comments in
+  order to support improvements to ESHost's dependency inferrence logic while
+  still passing in runtimes which do not yet support the proposed language
+  extension.
+esid: sec-moduleevaluation
+flags: [module]
+---*/
+
+import one from './import-assertion-1_FIXTURE.js'// assert {'':''};
+import two from "./import-assertion-2_FIXTURE.js"// assert {"":""};
+import './import-assertion-3_FIXTURE.js'// assert {'':''};
+import "./import-assertion-4_FIXTURE.js"// assert {"":""};
+
+assert.sameValue(one, 1);
+assert.sameValue(two, 2);