Annotate destructors to please coverity

Coverity flags this code as not handling exception that may happen in buffer().

My own analysis is that this can never happen because isBufferValid()
does check whether buffer_ is null.

Any insght appreciated. The commit should be expeanded to more cases, actually.

src/insets/Inset.h

@@ -112,8 +112,8 @@ public:
 	/// reset associated Buffer to null value
 	virtual void resetBuffer();
 	/// retrieve associated Buffer
-	virtual Buffer & buffer();
-	virtual Buffer const & buffer() const;
+	Buffer & buffer();
+	Buffer const & buffer() const;
 	/// Returns true if buffer_ actually points to a Buffer that has
 	/// been loaded into LyX and is still open. Note that this will
 	/// always return false for cloned Buffers. If you want to allow

src/insets/InsetBibitem.cpp

@@ -68,6 +68,9 @@ InsetBibitem::InsetBibitem(Buffer * buf, InsetCommandParams const & p)
 InsetBibitem::~InsetBibitem()
 {
 	if (isBufferLoaded())
+		/* Coverity believs that this may throw an exception, but
+		 * actually this code path is not taken when buffer_ == 0 */
+		// coverity[exn_spec_violation]
 		buffer().invalidateBibinfoCache();
 }
 

src/insets/InsetBibtex.cpp

@@ -68,7 +68,11 @@ InsetBibtex::InsetBibtex(Buffer * buf, InsetCommandParams const & p)
 InsetBibtex::~InsetBibtex()
 {
 	if (isBufferLoaded()) {
+		/* Coverity believs that this may throw an exception, but
+		 * actually this code path is not taken when buffer_ == 0 */
+		// coverity[exn_spec_violation]
 		buffer().invalidateBibfileCache();
+		// coverity[exn_spec_violation]
 		buffer().removeBiblioTempFiles();
 	}
 }

src/insets/InsetInclude.cpp

@@ -198,6 +198,9 @@ InsetInclude::InsetInclude(InsetInclude const & other)
 InsetInclude::~InsetInclude()
 {
 	if (isBufferLoaded())
+		/* Coverity believs that this may throw an exception, but
+		 * actually this code path is not taken when buffer_ == 0 */
+		// coverity[exn_spec_violation]
 		buffer().invalidateBibfileCache();
 	delete label_;
 }