Allow footnotes in floating tables via tablefootnote package

See #808.

(cherry picked from commit 5017a0a1c6)

lib/chkconfig.ltx

@@ -369,6 +369,7 @@
 \TestPackage{subfig}
 \TestPackage{subscript}
 \TestPackage{Sweave}
+\TestPackage{tablefootnote}
 \TestPackage{tcolorbox}
 \TestPackage{textcomp}
 \TestPackage{thswitch}

lib/doc/LaTeXConfig.lyx

@@ -5178,8 +5178,8 @@ Notes: The package
 footnote
 \family default
  is needed by \SpecialChar LyX
- to allow footnotes in non-floating tables and multi-page
- table headers and footers.
+ to allow footnotes in description items, non-floating tables
+ and multi-page table headers and footers.
  
 \end_layout
 
@@ -5307,6 +5307,35 @@ longtable
  to be able to output correctly multipage tables.
 \end_layout
 
+\begin_layout Subsection
+tablefootnote
+\end_layout
+
+\begin_layout Description
+Found: 
+\begin_inset Info
+type  "package"
+arg   "tablefootnote"
+\end_inset
+
+
+\end_layout
+
+\begin_layout Description
+CTAN: 
+\family typewriter
+macros/latex/contrib/tablefootnote/
+\end_layout
+
+\begin_layout Description
+Notes: The package 
+\family sans
+tablefootnote
+\family default
+ is needed by \SpecialChar LyX
+ to be able to output footnotes in floating tables.
+\end_layout
+
 \begin_layout Subsection
 textcomp
 \end_layout

lib/layouts/stdinsets.inc

@@ -122,6 +122,13 @@ InsetLayout Foot:InTitle
 	EndHTMLStyle
 End
 
+InsetLayout Foot:InFloatTable
+	CopyStyle             Foot
+	LatexName             tablefootnote
+	Requires              tablefootnote
+End
+
+
 InsetLayout Note:Comment
 	LabelString           Comment
 	LatexType             environment

src/LaTeXFeatures.cpp

@@ -975,6 +975,7 @@ char const * simplefeatures[] = {
 	"forest",
 	"varwidth",
 	"footnote",
+	"tablefootnote",
 };
 
 char const * bibliofeatures[] = {

src/insets/InsetFoot.cpp

@@ -34,13 +34,17 @@ using namespace std;
 namespace lyx {
 
 InsetFoot::InsetFoot(Buffer * buf)
-	: InsetFootlike(buf), intitle_(false)
+	: InsetFootlike(buf), intitle_(false), infloattable_(false)
 {}
 
 
 docstring InsetFoot::layoutName() const
 {
-	return intitle_ ? from_ascii("Foot:InTitle") : from_ascii("Foot");
+	if (intitle_)
+		return from_ascii("Foot:InTitle");
+	else if (infloattable_)
+		return from_ascii("Foot:InFloatTable");
+	return from_ascii("Foot");
 }
 
 
@@ -54,7 +58,13 @@ void InsetFoot::updateBuffer(ParIterator const & it, UpdateType utype)
 	}
 
 	intitle_ = false;
-	for (size_type sl = 0 ; sl < it.depth() ; ++ sl) {
+	infloattable_ = false;
+	bool intable = false;
+	if (it.innerInsetOfType(TABULAR_CODE) != 0)
+		intable = true;
+	if (it.innerInsetOfType(FLOAT_CODE) != 0)
+		infloattable_ = intable;
+	for (size_type sl = 0 ; sl < it.depth() ; ++sl) {
 		if (it[sl].text() && it[sl].paragraph().layout().intitle) {
 			intitle_ = true;
 			break;

src/insets/InsetFoot.h

@@ -48,6 +48,8 @@ private:
 	docstring custom_label_;
 	///
 	bool intitle_;
+	///
+	bool infloattable_;
 };
 
 

src/insets/InsetTabular.cpp

@@ -3427,7 +3427,7 @@ void Tabular::validate(LaTeXFeatures & features) const
 		// Tell footnote that we need a savenote
 		// environment in non-long tables or
 		// longtable headers/footers
-		if (!is_long_tabular)
+		else if (!is_long_tabular && !features.inFloat())
 			features.saveNoteEnv("tabular");
 		else if (!isValidRow(cellRow(cell)))
 			features.saveNoteEnv("longtable");