Revert of Roll Clang 243039:245342 (patchset #6 id:100001 of https://codereview.chromium.org/1294763003/ )

Reason for revert:
Broke StringHasherTest.StringHasher_addCharacters on WebKit Linux 32 bot.
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%2032/builds/39116

Original issue's description:
> Roll Clang 243039:245342
>
> BUG=518002
>
> Committed: https://crrev.com/bf0ed49cacad046649c521b77d925d60ae2c3243
> Cr-Commit-Position: refs/heads/master@{#344152}

TBR=thakis@chromium.org,hans@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=518002

Review URL: https://codereview.chromium.org/1286123007

Cr-Commit-Position: refs/heads/master@{#344177}

2 files changed, 28 insertions, 0 deletions

diff --git a/tools/clang/plugins/FindBadConstructsConsumer.cpp b/tools/clang/plugins/FindBadConstructsConsumer.cpp
index c99c389..1400171 100644
--- a/tools/clang/plugins/FindBadConstructsConsumer.cpp
+++ b/tools/clang/plugins/FindBadConstructsConsumer.cpp
@@ -641,10 +641,20 @@ FindBadConstructsConsumer::CheckRecordForRefcountIssue(
 
 // Returns true if |base| specifies one of the Chromium reference counted
 // classes (base::RefCounted / base::RefCountedThreadSafe).
+#if defined(LLVM_FORCE_HEAD_REVISION)
 bool FindBadConstructsConsumer::IsRefCounted(
     const CXXBaseSpecifier* base,
     CXXBasePath& path) {
   FindBadConstructsConsumer* self = this;
+#else
+// static
+bool FindBadConstructsConsumer::IsRefCountedCallback(
+    const CXXBaseSpecifier* base,
+    CXXBasePath& path,
+    void* user_data) {
+  FindBadConstructsConsumer* self =
+      static_cast<FindBadConstructsConsumer*>(user_data);
+#endif
   const TemplateSpecializationType* base_type =
       dyn_cast<TemplateSpecializationType>(
           UnwrapType(base->getType().getTypePtr()));
@@ -730,11 +740,17 @@ void FindBadConstructsConsumer::CheckRefCountedDtors(
 
   // Determine if the current type is even ref-counted.
   CXXBasePaths refcounted_path;
+#if defined(LLVM_FORCE_HEAD_REVISION)
   if (!record->lookupInBases(
           [this](const CXXBaseSpecifier* base, CXXBasePath& path) {
             return IsRefCounted(base, path);
           },
           refcounted_path)) {
+#else
+  if (!record->lookupInBases(&FindBadConstructsConsumer::IsRefCountedCallback,
+                             this,
+                             refcounted_path)) {
+#endif
     return;  // Class does not derive from a ref-counted base class.
   }
 
@@ -784,12 +800,18 @@ void FindBadConstructsConsumer::CheckRefCountedDtors(
   // Find all public destructors. This will record the class hierarchy
   // that leads to the public destructor in |dtor_paths|.
   CXXBasePaths dtor_paths;
+#if defined(LLVM_FORCE_HEAD_REVISION)
   if (!record->lookupInBases(
           [](const CXXBaseSpecifier* base, CXXBasePath& path) {
             // TODO(thakis): Inline HasPublicDtorCallback() after clang roll.
             return HasPublicDtorCallback(base, path, nullptr);
           },
           dtor_paths)) {
+#else
+  if (!record->lookupInBases(&FindBadConstructsConsumer::HasPublicDtorCallback,
+                             nullptr,
+                             dtor_paths)) {
+#endif
     return;
   }
 
diff --git a/tools/clang/plugins/FindBadConstructsConsumer.h b/tools/clang/plugins/FindBadConstructsConsumer.h
index 8f8fc87..7ad0215 100644
--- a/tools/clang/plugins/FindBadConstructsConsumer.h
+++ b/tools/clang/plugins/FindBadConstructsConsumer.h
@@ -85,8 +85,14 @@ class FindBadConstructsConsumer
   static RefcountIssue CheckRecordForRefcountIssue(
       const clang::CXXRecordDecl* record,
       clang::SourceLocation& loc);
+#if defined(LLVM_FORCE_HEAD_REVISION)
   bool IsRefCounted(const clang::CXXBaseSpecifier* base,
                     clang::CXXBasePath& path);
+#else
+  static bool IsRefCountedCallback(const clang::CXXBaseSpecifier* base,
+                                   clang::CXXBasePath& path,
+                                   void* user_data);
+#endif
   static bool HasPublicDtorCallback(const clang::CXXBaseSpecifier* base,
                                     clang::CXXBasePath& path,
                                     void* user_data);