Bug 1794644 - Part 2: Mark `StaticRWLock` as `MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS`, r=xpcom-reviewers,kmag

The original use in rlbox which made having this annotation impossible is no
longer necessary as it was removed in the previous part.

Differential Revision: https://phabricator.services.mozilla.com/D159085

extensions/spellcheck/hunspell/glue/mozHunspellRLBoxHost.cpp

@@ -81,7 +81,7 @@ bool mozHunspellFileMgrHost::GetLine(std::string& aResult) {
 /* static */
 uint32_t mozHunspellCallbacks::sCurrentFreshId = 0;
 /* static */
-mozilla::detail::StaticRWLock mozHunspellCallbacks::sFileMgrMapLock;
+mozilla::StaticRWLock mozHunspellCallbacks::sFileMgrMapLock;
 /* static */
 std::map<uint32_t, std::unique_ptr<mozHunspellFileMgrHost>>
     mozHunspellCallbacks::sFileMgrMap;
@@ -90,13 +90,13 @@ std::set<nsCString> mozHunspellCallbacks::sFileMgrAllowList;
 
 /* static */
 void mozHunspellCallbacks::AllowFile(const nsCString& aFilename) {
-  mozilla::detail::StaticAutoWriteLock lock(sFileMgrMapLock);
+  mozilla::StaticAutoWriteLock lock(sFileMgrMapLock);
   sFileMgrAllowList.insert(aFilename);
 }
 
 /* static */
 void mozHunspellCallbacks::Clear() {
-  mozilla::detail::StaticAutoWriteLock lock(sFileMgrMapLock);
+  mozilla::StaticAutoWriteLock lock(sFileMgrMapLock);
   sCurrentFreshId = 0;
   sFileMgrMap.clear();
   sFileMgrAllowList.clear();
@@ -106,7 +106,7 @@ void mozHunspellCallbacks::Clear() {
 tainted_hunspell<uint32_t> mozHunspellCallbacks::CreateFilemgr(
     rlbox_sandbox_hunspell& aSandbox,
     tainted_hunspell<const char*> t_aFilename) {
-  mozilla::detail::StaticAutoWriteLock lock(sFileMgrMapLock);
+  mozilla::StaticAutoWriteLock lock(sFileMgrMapLock);
 
   return t_aFilename.copy_and_verify_string(
       [&](std::unique_ptr<char[]> aFilename) {
@@ -146,7 +146,7 @@ uint32_t mozHunspellCallbacks::GetFreshId() {
 /* static */
 mozHunspellFileMgrHost& mozHunspellCallbacks::GetMozHunspellFileMgrHost(
     tainted_hunspell<uint32_t> t_aFd) {
-  mozilla::detail::StaticAutoReadLock lock(sFileMgrMapLock);
+  mozilla::StaticAutoReadLock lock(sFileMgrMapLock);
   uint32_t aFd = t_aFd.copy_and_verify([](uint32_t aFd) { return aFd; });
   auto iter = sFileMgrMap.find(aFd);
   MOZ_RELEASE_ASSERT(iter != sFileMgrMap.end());
@@ -193,7 +193,7 @@ tainted_hunspell<int> mozHunspellCallbacks::GetLineNum(
 /* static */
 void mozHunspellCallbacks::DestructFilemgr(rlbox_sandbox_hunspell& aSandbox,
                                            tainted_hunspell<uint32_t> t_aFd) {
-  mozilla::detail::StaticAutoWriteLock lock(sFileMgrMapLock);
+  mozilla::StaticAutoWriteLock lock(sFileMgrMapLock);
   uint32_t aFd = t_aFd.copy_and_verify([](uint32_t aFd) { return aFd; });
 
   auto iter = sFileMgrMap.find(aFd);

extensions/spellcheck/hunspell/glue/mozHunspellRLBoxHost.h

@@ -102,7 +102,7 @@ class mozHunspellCallbacks {
   /**
    * Reader-writer lock for the sFileMgrMap
    */
-  static mozilla::detail::StaticRWLock sFileMgrMapLock;
+  static mozilla::StaticRWLock sFileMgrMapLock;
   /**
    * Tracks the next possibly unused id for sFileMgrMap
    */

xpcom/threads/RWLock.h

@@ -11,6 +11,7 @@
 
 #include "mozilla/Assertions.h"
 #include "mozilla/Atomics.h"
+#include "mozilla/Attributes.h"
 #include "mozilla/BlockingResourceBase.h"
 #include "mozilla/PlatformRWLock.h"
 #include "mozilla/ThreadSafety.h"
@@ -181,16 +182,7 @@ typedef BaseAutoTryWriteLock<RWLock> AutoTryWriteLock;
 // calls to WriteLock() and WriteUnlock().
 typedef BaseAutoWriteLock<RWLock> AutoWriteLock;
 
-// XXX: normally we would define StaticRWLock as
-// MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS, but the contexts in which it
-// is used (e.g. member variables in a third-party library) are non-trivial
-// to modify to properly declare everything at static scope.  As those
-// third-party libraries are the only clients, put it behind the detail
-// namespace to discourage other (possibly erroneous) uses from popping up.
-
-namespace detail {
-
-class MOZ_CAPABILITY StaticRWLock {
+class MOZ_ONLY_USED_TO_AVOID_STATIC_CONSTRUCTORS MOZ_CAPABILITY StaticRWLock {
  public:
   // In debug builds, check that mLock is initialized for us as we expect by
   // the compiler.  In non-debug builds, don't declare a constructor so that
@@ -245,8 +237,6 @@ typedef BaseAutoReadLock<StaticRWLock> StaticAutoReadLock;
 typedef BaseAutoTryWriteLock<StaticRWLock> StaticAutoTryWriteLock;
 typedef BaseAutoWriteLock<StaticRWLock> StaticAutoWriteLock;
 
-}  // namespace detail
-
 }  // namespace mozilla
 
 #endif  // mozilla_RWLock_h