packaging: detect vc_redist and prevent reinstallation

Change-Id: I149d58da06d6ab2ae8ea712da9a39374ac921cf1

ring.nsi

@@ -196,15 +196,16 @@ section "install"
         WriteRegStr HKCR "ring" "URL Protocol" "$\"$\""
         WriteRegStr HKCR "ring\DefaultIcon" "" "$\"$INSTDIR\Jami.exe,1$\""
         WriteRegStr HKCR "ring\shell\open\command" "" "$\"$INSTDIR\Jami.exe$\" $\"%1$\""
-        # vcredist install (the check would work if uninstalling would remove the REG key)
-        #{If} ${RunningX64}
-        #    ReadRegStr $1 HKLM "SOFTWARE\WOW6432Node\Microsoft\VisualStudio\14.0\VC\Runtimes\x64" "Bld"
-        #    StrCmp $1 27012 vcredist_installed
-        #${Else}
-        #    ReadRegStr $1 HKLM "SOFTWARE\WOW6432Node\Microsoft\VisualStudio\14.0\VC\Runtimes\x86" "Bld"
-        #    StrCmp $1 27012 vcredist_installed
-        #${EndIf}
-        ExecWait "vc_redist.x64.exe /install /passive /norestart"
+        # vcredist install (this check may not work if the vc_redist is uninstalled by the user as
+        # uninstallation does not remove the REG key
+        {If} ${RunningX64}
+            ReadRegStr $1 HKLM "SOFTWARE\WOW6432Node\Microsoft\VisualStudio\14.0\VC\Runtimes\x64" "Bld"
+            StrCmp $1 27012 vcredist_installed
+        ${Else}
+            ReadRegStr $1 HKLM "SOFTWARE\WOW6432Node\Microsoft\VisualStudio\14.0\VC\Runtimes\x86" "Bld"
+            StrCmp $1 27012 vcredist_installed
+        ${EndIf}
+        ExecWait "vc_redist.x64.exe /install /norestart"
         #vcredist_installed:
 sectionEnd