test=develop, uninstall protobuf on linux brefore install latest version of it

paddle/scripts/paddle_build.sh

@@ -88,6 +88,7 @@ function cmake_gen() {
             -DPYTHON_INCLUDE_DIR:PATH=/Library/Frameworks/Python.framework/Versions/3.5/include/python3.5m/
             -DPYTHON_LIBRARY:FILEPATH=/Library/Frameworks/Python.framework/Versions/3.5/lib/libpython3.5m.dylib"
                 WITH_FLUID_ONLY=${WITH_FLUID_ONLY:-ON}
+                pip3.5 uninstall -y protobuf
                 pip3.5 install --user -r ${PADDLE_ROOT}/python/requirements.txt
             else
                 exit 1
@@ -101,6 +102,7 @@ function cmake_gen() {
             -DPYTHON_INCLUDE_DIR:PATH=/Library/Frameworks/Python.framework/Versions/3.6/include/python3.6m/
             -DPYTHON_LIBRARY:FILEPATH=/Library/Frameworks/Python.framework/Versions/3.6/lib/libpython3.6m.dylib"
                 WITH_FLUID_ONLY=${WITH_FLUID_ONLY:-ON}
+                pip3.6 uninstall -y protobuf
                 pip3.6 install --user -r ${PADDLE_ROOT}/python/requirements.txt
             else
                 exit 1
@@ -114,6 +116,7 @@ function cmake_gen() {
             -DPYTHON_INCLUDE_DIR:PATH=/Library/Frameworks/Python.framework/Versions/3.7/include/python3.7m/
             -DPYTHON_LIBRARY:FILEPATH=/Library/Frameworks/Python.framework/Versions/3.7/lib/libpython3.7m.dylib"
                 WITH_FLUID_ONLY=${WITH_FLUID_ONLY:-ON}
+                pip3.7 uninstall -y protobuf
                 pip3.7 install --user -r ${PADDLE_ROOT}/python/requirements.txt
             else
                 exit 1
@@ -128,6 +131,7 @@ function cmake_gen() {
                 PYTHON_FLAGS="-DPYTHON_EXECUTABLE:FILEPATH=/opt/python/cp27-cp27m/bin/python
             -DPYTHON_INCLUDE_DIR:PATH=/opt/python/cp27-cp27m/include/python2.7
             -DPYTHON_LIBRARIES:FILEPATH=/opt/_internal/cpython-2.7.11-ucs2/lib/libpython2.7.so"
+                pip uninstall -y protobuf
                 pip install -r ${PADDLE_ROOT}/python/requirements.txt
             elif [ "$1" == "cp27-cp27mu" ]; then
                 export LD_LIBRARY_PATH=/opt/_internal/cpython-2.7.11-ucs4/lib:${LD_LIBRARY_PATH#/opt/_internal/cpython-2.7.11-ucs2/lib:}
@@ -135,6 +139,7 @@ function cmake_gen() {
                 PYTHON_FLAGS="-DPYTHON_EXECUTABLE:FILEPATH=/opt/python/cp27-cp27mu/bin/python
             -DPYTHON_INCLUDE_DIR:PATH=/opt/python/cp27-cp27mu/include/python2.7
             -DPYTHON_LIBRARIES:FILEPATH=/opt/_internal/cpython-2.7.11-ucs4/lib/libpython2.7.so"
+                pip uninstall -y protobuf
                 pip install -r ${PADDLE_ROOT}/python/requirements.txt
             elif [ "$1" == "cp35-cp35m" ]; then
                 export LD_LIBRARY_PATH=/opt/_internal/cpython-3.5.1/lib/:${LD_LIBRARY_PATH}
@@ -142,6 +147,7 @@ function cmake_gen() {
                 export PYTHON_FLAGS="-DPYTHON_EXECUTABLE:FILEPATH=/opt/_internal/cpython-3.5.1/bin/python3
             -DPYTHON_INCLUDE_DIR:PATH=/opt/_internal/cpython-3.5.1/include/python3.5m
             -DPYTHON_LIBRARIES:FILEPATH=/opt/_internal/cpython-3.5.1/lib/libpython3.so"
+                pip3.5 uninstall -y protobuf
                 pip3.5 install -r ${PADDLE_ROOT}/python/requirements.txt
             elif [ "$1" == "cp36-cp36m" ]; then
                 export LD_LIBRARY_PATH=/opt/_internal/cpython-3.6.0/lib/:${LD_LIBRARY_PATH}
@@ -149,6 +155,7 @@ function cmake_gen() {
                 export PYTHON_FLAGS="-DPYTHON_EXECUTABLE:FILEPATH=/opt/_internal/cpython-3.6.0/bin/python3
             -DPYTHON_INCLUDE_DIR:PATH=/opt/_internal/cpython-3.6.0/include/python3.6m
             -DPYTHON_LIBRARIES:FILEPATH=/opt/_internal/cpython-3.6.0/lib/libpython3.so"
+                pip3.6 uninstall -y protobuf
                 pip3.6 install -r ${PADDLE_ROOT}/python/requirements.txt
             elif [ "$1" == "cp37-cp37m" ]; then
                 export LD_LIBRARY_PATH=/opt/_internal/cpython-3.7.0/lib/:${LD_LIBRARY_PATH}
@@ -156,6 +163,7 @@ function cmake_gen() {
                 export PYTHON_FLAGS="-DPYTHON_EXECUTABLE:FILEPATH=/opt/_internal/cpython-3.7.0/bin/python3.7
             -DPYTHON_INCLUDE_DIR:PATH=/opt/_internal/cpython-3.7.0/include/python3.7m
             -DPYTHON_LIBRARIES:FILEPATH=/opt/_internal/cpython-3.7.0/lib/libpython3.so"
+                pip3.7 uninstall -y protobuf
                 pip3.7 install -r ${PADDLE_ROOT}/python/requirements.txt
            fi
         fi