[LyX/master] Use explicit default syntax (C++11).

[Richard Kimberly Heck]

commit 3d46cc302bcff979a874ef2ea9c8a56a85aaec77
Author: Richard Kimberly Heck <rikiheck at lyx.org>
Date:   Tue Oct 6 20:31:11 2020 -0400

    Use explicit default syntax (C++11).
    
    Thanks to Jos'e for noticing this option.
---
 src/insets/InsetTabular.cpp |    8 --------
 src/insets/InsetTabular.h   |    8 ++------
 2 files changed, 2 insertions(+), 14 deletions(-)

diff --git a/src/insets/InsetTabular.cpp b/src/insets/InsetTabular.cpp
index 29858c5..afd2976 100644
--- a/src/insets/InsetTabular.cpp
+++ b/src/insets/InsetTabular.cpp
@@ -4205,14 +4205,6 @@ InsetTableCell::InsetTableCell(Buffer * buf)
 	  isMultiColumn(false), isMultiRow(false), contentAlign(LYX_ALIGN_CENTER)
 {}
 
-InsetTableCell::InsetTableCell(InsetTableCell const & in) : InsetText(in)
-{
-	isFixedWidth = in.isFixedWidth;
-	isMultiColumn = in.isMultiColumn;
-	isMultiRow = in.isMultiRow;
-	contentAlign = in.contentAlign;
-}
-
 bool InsetTableCell::forcePlainLayout(idx_type) const
 {
 	return isMultiRow || (isMultiColumn && !isFixedWidth);
diff --git a/src/insets/InsetTabular.h b/src/insets/InsetTabular.h
index 33d4974..3db458a 100644
--- a/src/insets/InsetTabular.h
+++ b/src/insets/InsetTabular.h
@@ -55,9 +55,8 @@ public:
 	///
 	explicit InsetTableCell(Buffer * buf);
 	/// We need this since generation of the default is deprecated
-	/// (since we declare the assignment constucture below).
-	/// Please make sure to adjust it if you add members!
-	InsetTableCell(InsetTableCell const &);
+	/// (since we declare the assignment constuctor below).
+	InsetTableCell(InsetTableCell const & in) = default;
 	///
 	InsetCode lyxCode() const override { return CELL_CODE; }
 	///
@@ -118,9 +117,6 @@ private:
 	// be quite slow.
 	// So, well, if someone can do better, please do!
 	// --rkh
-	//
-	// NOTE: Make sure to adapt the construcors (especially the copy
-	// constructor) if you add members!
 	///
 	bool isFixedWidth;
 	///