Bug 1711126 - The module index in the third-party modules ping may be -1. r=mhowell

This patch updates the regex pattern to match data where the module index of
a callstack is -1 or a non-negative integer.  -1 is legitimately set in
`CreateJSStackObject` when the frame address is not within any module in the
module list.

If the pattern did not match in debug build, calling `toBoolean()` hit the
assert because `matchResult` was not a boolean but null.  This patch fixes
that problem, too.

Differential Revision: https://phabricator.services.mozilla.com/D122020

toolkit/xre/test/gtest/TestUntrustedModules.cpp

@@ -236,7 +236,7 @@ class UntrustedModulesFixture : public TelemetryTestFixture {
     // On match, with aOnlyMatch = true, ExecuteRegExpNoStatics returns boolean
     // true.  If no match, ExecuteRegExpNoStatics returns Null.
     EXPECT_TRUE(matchResult.isBoolean() && matchResult.toBoolean());
-    if (!matchResult.toBoolean()) {
+    if (!matchResult.isBoolean() || !matchResult.toBoolean()) {
       // If match failed, print out the actual JSON kindly.
       wprintf(L"JSON: %s\n", json.get());
       wprintf(L"RE: %s\n", aPattern);
@@ -366,8 +366,8 @@ BOOL CALLBACK UntrustedModulesFixture::InitialModuleLoadOnce(PINIT_ONCE, void*,
     u"\"combinedStacks\":{" \
       u"\"memoryMap\":\\[\\[\"\\w+\\.\\w+\",\"[0-9A-Z]+\"\\]" \
         u"(,\\[\"\\w+\\.\\w+\",\"[0-9A-Z]+\\\"\\])*\\]," \
-      u"\"stacks\":\\[\\[\\[\\d+,\\d+\\]" \
-        u"(,\\[\\d+,\\d+\\])*\\]\\]}}"
+      u"\"stacks\":\\[\\[\\[(-1|\\d+),\\d+\\]" \
+        u"(,\\[(-1|\\d+),\\d+\\])*\\]\\]}}"
 
 TEST_F(UntrustedModulesFixture, Serialize) {
   // clang-format off