[LyX/master] Let "provides [fontspec|listings|subfig] 1" work.

[Richard Heck]

commit f46a52d97ff5528445c8d68d70478379f55774d9
Author: Richard Heck <rgh...@lyx.org>
Date:   Tue Jun 21 10:50:42 2016 -0400

    Let "provides [fontspec|listings|subfig] 1" work.
---
 src/BufferParams.cpp |    7 ++++---
 1 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/BufferParams.cpp b/src/BufferParams.cpp
index 373eee5..d2218e0 100644
--- a/src/BufferParams.cpp
+++ b/src/BufferParams.cpp
@@ -1589,7 +1589,8 @@ bool BufferParams::writeLaTeX(otexstream & os, 
LaTeXFeatures & features,
                os << from_ascii(ams);
 
        if (useNonTeXFonts) {
-               os << "\\usepackage{fontspec}\n";
+               if (!features.isProvided("fontspec"))
+                       os << "\\usepackage{fontspec}\n";
                if (features.mustProvide("unicode-math")
                    && features.isAvailable("unicode-math"))
                        os << "\\usepackage{unicode-math}\n";
@@ -2054,7 +2055,7 @@ bool BufferParams::writeLaTeX(otexstream & os, 
LaTeXFeatures & features,
        // koma's own caption commands are used instead of caption. We
        // use \PassOptionsToPackage here because the user could have
        // already loaded subfig in the preamble.
-       if (features.isRequired("subfig")) {
+       if (features.mustProvide("subfig")) {
                atlyxpreamble += "\\@ifundefined{showcaptionsetup}{}{%\n"
                        " \\PassOptionsToPackage{caption=false}{subfig}}\n"
                        "\\usepackage{subfig}\n";
@@ -2115,7 +2116,7 @@ bool BufferParams::writeLaTeX(otexstream & os, 
LaTeXFeatures & features,
        }
        if (features.isRequired("bicaption"))
                lyxpreamble += "\\usepackage{bicaption}\n";
-       if (!listings_params.empty() || features.isRequired("listings"))
+       if (!listings_params.empty() || features.mustProvide("listings"))
                lyxpreamble += "\\usepackage{listings}\n";
        if (!listings_params.empty()) {
                lyxpreamble += "\\lstset{";