Reintroduce silent mode for building PhantomJS 2.

https://github.com/ariya/phantomjs/issues/11880
https://github.com/ariya/phantomjs/issues/10448

src/qt/preconfig.sh

@@ -64,6 +64,8 @@ QT_CFG+=' -D QT_NO_STYLE_CLEANLOOKS'
 QT_CFG+=' -D QT_NO_STYLE_MOTIF'
 QT_CFG+=' -D QT_NO_STYLE_PLASTIQUE'
 
+SILENT=''
+
 until [ -z "$1" ]; do
     case $1 in
         "--qt-config")
@@ -74,6 +76,10 @@ until [ -z "$1" ]; do
             shift
             COMPILE_JOBS=$1
             shift;;
+        "--silent")
+            SILENT='-s'
+            QT_CFG+=" -silent"
+            shift;;
         "--help")
             echo "Usage: $0 [--qt-config CONFIG] [--jobs NUM]"
             echo
@@ -92,6 +98,13 @@ done
 # For parallelizing the bootstrapping process, e.g. qmake and friends.
 export MAKEFLAGS=-j$COMPILE_JOBS
 
-./configure -prefix $PWD $QT_CFG
-make -j$COMPILE_JOBS
-popd
+if [ -z "$SILENT" ]; then
+    ./configure -prefix $PWD $QT_CFG
+else
+    echo "Setting up Qt. Please wait..."
+    ./configure -prefix $PWD $QT_CFG &> /dev/null
+fi
+
+echo
+echo "Building Qt and WebKit. Please wait..."
+make -j$COMPILE_JOBS $SILENT