https://blog.qt.io/blog/2015/10/15/qt-5-5-1-released/?replyt

I can confirm I successfully built Qt 5.5.1 (with QtWebkit) with Visual Studio 2015 without making QtCore link against ICU by not giving Qt's configure the "-icu" flag.

However,

You two are saying QtWebkit doesn't need ICU. Indeed I can find ICU inside:
  - qtwebkit/Source/JavascriptCore/icu/
  - qtwebkit/Source/WebCore/icu
  - qtwebkit/Source/WTF/icu

But, if I don't build ICU myself, don't add it to %INCLUDE% and %LIB%, and don't use Qt's -icu configure flag, then compiling Qt doesn't build Qt5WebKit.dll. I just tried it again, by commenting out the build of ICU in the following .bat file: http://pempek.net/files/compiling-qt-5-5-1-with-visual-studio-2015/build-x64.bat

Really I believe it's a good idea you take a blank PC, install Visual Studio 2015, download your own qt-everywhere-opensource-src-5.5.1.zip source drop and write down all the steps one has to make in order to compile it full fledged (with ANGLE, QtWebkit etc..) just like you would do when you provide pre-built binaries. Write down everything, from Visual Studio 2015 installation options to any required prerequisite that needs to be installed and added to %PATH%.