[libcxx][docs] Remove completed issues from TODO.TXT

Remove tasks listed that refer to papers or issues that are marked complete in
`libcxx/docs/Status/Cxx17Papers.csv` or `libcxx/docs/Status/Cxx17Issues.csv`

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D108856

Author: JoeLoser

libcxx/TODO.TXT

@@ -16,60 +16,9 @@ Test Suite Tasks
 * Improve the quality and portability of the locale test data.
 * Convert failure tests to use Clang Verify.
 
-Filesystem Tasks
-================
-* P0492r2 - Implement National body comments for Filesystem
-    * INCOMPLETE - US 25: has_filename() is equivalent to just !empty()
-    * INCOMPLETE - US 31: Everything is defined in terms of one implicit host system
-    * INCOMPLETE - US 32: Meaning of 27.10.2.1 unclear
-    * INCOMPLETE - US 33: Definition of canonical path problematic
-    * INCOMPLETE - US 34: Are there attributes of a file that are not an aspect of the file system?
-    * INCOMPLETE - US 35: What synchronization is required to avoid a file system race?
-    * INCOMPLETE - US 36: Symbolic links themselves are attached to a directory via (hard) links
-    * INCOMPLETE - US 37: The term “redundant current directory (dot) elements” is not defined
-    * INCOMPLETE - US 38: Duplicates §17.3.16
-    * INCOMPLETE - US 39: Remove note: Dot and dot-dot are not directories
-    * INCOMPLETE - US 40: Not all directories have a parent.
-    * INCOMPLETE - US 41: The term “parent directory” for a (non-directory) file is unusual
-    * INCOMPLETE - US 42: Pathname resolution does not always resolve a symlink
-    * INCOMPLETE - US 43: Concerns about encoded character types
-    * INCOMPLETE - US 44: Definition of path in terms of a string requires leaky abstraction
-    * INCOMPLETE - US 45: Generic format portability compromised by unspecified root-name
-    * INCOMPLETE - US 46: filename can be empty so productions for relative-path are redundant
-    * INCOMPLETE - US 47: “.” and “..” already match the name production
-    * INCOMPLETE - US 48: Multiple separators are often meaningful in a root-name
-    * INCOMPLETE - US 49: What does “method of conversion method” mean?
-    * INCOMPLETE - US 50: 27.10.8.1 ¶ 1.4 largely redundant with ¶ 1.3
-    * INCOMPLETE - US 51: Failing to add / when appending empty string prevents useful apps
-    * INCOMPLETE - US 52: remove_filename() postcondition is not by itself a definition
-    * INCOMPLETE - US 53: remove_filename()'s name does not correspond to its behavior
-    * INCOMPLETE - US 54: remove_filename() is broken
-    * INCOMPLETE - US 55: replace_extension()'s use of path as parameter is inappropriate
-    * INCOMPLETE - US 56: Remove replace_extension()'s conditional addition of period
-    * INCOMPLETE - US 57: On Windows, absolute paths will sort in among relative paths
-    * INCOMPLETE - US 58: parent_path() behavior for root paths is useless
-    * INCOMPLETE - US 59: filename() returning path for single path components is bizarre
-    * INCOMPLETE - US 60: path("/foo/").filename()==path(".") is surprising
-    * INCOMPLETE - US 61: Leading dots in filename() should not begin an extension
-    * INCOMPLETE - US 62: It is important that stem()+extension()==filename()
-    * INCOMPLETE - US 63: lexically_normal() inconsistently treats trailing "/" but not "/.." as directory
-    * INCOMPLETE - US 73, CA 2: root-name is effectively implementation defined
-    * INCOMPLETE - US 74, CA 3: The term “pathname” is ambiguous in some contexts
-    * INCOMPLETE - US 75, CA 4: Extra flag in path constructors is needed
-    * INCOMPLETE - US 76, CA 5: root-name definition is over-specified.
-    * INCOMPLETE - US 77, CA 6: operator/ and other appends not useful if arg has root-name
-    * INCOMPLETE - US 78, CA 7: Member absolute() in 27.10.4.1 is overspecified for non-POSIX-like O/S
-    * INCOMPLETE - US 79, CA 8: Some operation functions are overspecified for implementation-defined file types
-    * INCOMPLETE - US 185: Fold error_code and non-error_code signatures into one signature
-    * INCOMPLETE - FI 14: directory_entry comparisons are members
-    * INCOMPLETE - Late 36: permissions() error_code overload should be noexcept
-    * INCOMPLETE - Late 37: permissions() actions should be separate parameter
-    * INCOMPLETE - Late 42: resize_file() Postcondition missing argument
-
 Misc Tasks
 ==========
 * Find all sequences of >2 underscores and eradicate them.
 * run clang-tidy on libc++
 * Document the "conditionally-supported" bits of libc++
-* Look at basic_string's move assignment operator, re LWG 2063 and POCMA
 * Put a static_assert in std::allocator to deny const/volatile types (LWG 2447)