Fix compilation with system double-conversion

A recent patch made it so we don't need to keep patching the includes
of the sources. However it changed how we use double-conversion ourselves
which meant that system installs would no longer work. Keeping an extra
directory and adding another INCLUDE_DIRECTORY fixes both of our problems.

Amends dca74b45a3

Fixes: QTBUG-90961
Change-Id: If17aa1670535867343374eec846055441592f36b
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

src/corelib/CMakeLists.txt

@@ -747,27 +747,28 @@ qt_internal_extend_target(Core CONDITION QT_FEATURE_system_doubleconversion
 
 qt_internal_extend_target(Core CONDITION QT_FEATURE_doubleconversion AND NOT QT_FEATURE_system_doubleconversion
     SOURCES
-        ../3rdparty/double-conversion/bignum.cc
-        ../3rdparty/double-conversion/bignum-dtoa.cc
-        ../3rdparty/double-conversion/bignum-dtoa.h
-        ../3rdparty/double-conversion/bignum.h
-        ../3rdparty/double-conversion/cached-powers.cc
-        ../3rdparty/double-conversion/cached-powers.h
-        ../3rdparty/double-conversion/diy-fp.h
-        ../3rdparty/double-conversion/double-conversion.h
-        ../3rdparty/double-conversion/double-to-string.cc
-        ../3rdparty/double-conversion/double-to-string.h
-        ../3rdparty/double-conversion/fast-dtoa.cc
-        ../3rdparty/double-conversion/fast-dtoa.h
-        ../3rdparty/double-conversion/fixed-dtoa.cc
-        ../3rdparty/double-conversion/fixed-dtoa.h
-        ../3rdparty/double-conversion/ieee.h
-        ../3rdparty/double-conversion/string-to-double.cc
-        ../3rdparty/double-conversion/string-to-double.h
-        ../3rdparty/double-conversion/strtod.cc
-        ../3rdparty/double-conversion/strtod.h
-        ../3rdparty/double-conversion/utils.h
+        ../3rdparty/double-conversion/double-conversion/bignum.cc
+        ../3rdparty/double-conversion/double-conversion/bignum-dtoa.cc
+        ../3rdparty/double-conversion/double-conversion/bignum-dtoa.h
+        ../3rdparty/double-conversion/double-conversion/bignum.h
+        ../3rdparty/double-conversion/double-conversion/cached-powers.cc
+        ../3rdparty/double-conversion/double-conversion/cached-powers.h
+        ../3rdparty/double-conversion/double-conversion/diy-fp.h
+        ../3rdparty/double-conversion/double-conversion/double-conversion.h
+        ../3rdparty/double-conversion/double-conversion/double-to-string.cc
+        ../3rdparty/double-conversion/double-conversion/double-to-string.h
+        ../3rdparty/double-conversion/double-conversion/fast-dtoa.cc
+        ../3rdparty/double-conversion/double-conversion/fast-dtoa.h
+        ../3rdparty/double-conversion/double-conversion/fixed-dtoa.cc
+        ../3rdparty/double-conversion/double-conversion/fixed-dtoa.h
+        ../3rdparty/double-conversion/double-conversion/ieee.h
+        ../3rdparty/double-conversion/double-conversion/string-to-double.cc
+        ../3rdparty/double-conversion/double-conversion/string-to-double.h
+        ../3rdparty/double-conversion/double-conversion/strtod.cc
+        ../3rdparty/double-conversion/double-conversion/strtod.h
+        ../3rdparty/double-conversion/double-conversion/utils.h
     INCLUDE_DIRECTORIES
+        ../3rdparty/double-conversion/double-conversion
         ../3rdparty/double-conversion
 )
 

src/corelib/text/qdoublescanprint_p.h

@@ -148,7 +148,7 @@ inline int qDoubleSnprintf(char *buf, size_t buflen, locale_t locale, const char
 QT_END_NAMESPACE
 
 #  else // !QT_NO_DOUBLECONVERSION
-#    include <double-conversion.h>
+#    include <double-conversion/double-conversion.h>
 #    define QT_CLOCALE_HOLDER
 #  endif // QT_NO_DOUBLECONVERSION
 #endif // QT_BOOTSTRAPPED