C++: Fix unit-tests for MatchingText

BackwardScanner required more investigation and this is
the better fix than 413c66ec.

Change-Id: I651a7b416b549cc4a0e086873262d04409a7448e
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/libs/cplusplus/BackwardsScanner.cpp

@@ -124,6 +124,11 @@ int BackwardsScanner::size() const
     return _tokens.size();
 }
 
+int BackwardsScanner::offset() const
+{
+    return _offset;
+}
+
 int BackwardsScanner::startOfMatchingBrace(int index) const
 {
     const BackwardsScanner &tk = *this;

src/libs/cplusplus/BackwardsScanner.h

@@ -66,6 +66,7 @@ public:
     int startOfBlock(int index) const;
 
     int size() const;
+    int offset() const;
 
     static int previousBlockState(const QTextBlock &block);
 

src/libs/cplusplus/MatchingText.cpp

@@ -324,7 +324,7 @@ static bool isRecordLikeToken(const Token &token)
 
 static bool isRecordLikeToken(const BackwardsScanner &tokens, int index)
 {
-    if (index < tokens.size() - 1)
+    if (index + tokens.offset() < tokens.size() - 1)
         return isRecordLikeToken(tokens[index]);
     return false;
 }
@@ -347,7 +347,7 @@ static bool recordLikeMightFollowToken(const Token &token)
 
 static bool isAfterRecordLikeDefinition(const BackwardsScanner &tokens, int index)
 {
-    for (; index >= 0; --index) {
+    for (;; --index) {
         if (recordLikeHasToFollowToken(tokens[index]))
             return isRecordLikeToken(tokens, index + 1);