function markDeprecatedNodes(oSymbol) {
		// 1. If the symbol is deprecated all content in it should be also deprecated
		if (oSymbol.deprecated) {
			// 2. If all content in the symbol is deprecated, flag should explicitly be passed to its child nodes.
			propagateFlags(oSymbol, { bAllContentDeprecated: true });
		} else {
			// 3. If all children are deprecated, then the parent is marked as content-deprecated
			oSymbol.bAllContentDeprecated = !!oSymbol.nodes && oSymbol.nodes.every((node) => node.bAllContentDeprecated);
		}
	}
Sets the <code>bAllContentDeprecated</code> flag of each symbol

The <code>bAllContentDeprecated</code> flag differs from the already existing <code>deprecated</code> flag
in the following respect:

    1) if a node is deprecated => all its children should be marked as <code>bAllContentDeprecated</code>
       (even if not explicitly deprecated in their JSDoc)
    2) if all children of the node are deprecated => that node should also be marked as <code>bAllContentDeprecated</code>
       (even if not explicitly deprecated in its JSDoc)
    3) if a node is explicitly deprecated in its JSDoc => it should also be marked as <code>bAllContentDeprecated</code>
       (for consistency)

@param oSymbol