Added more comments to tooling::Replacements.

[ioeric]

Summary

Also test phabricator commit processing.

[ioeric]

Since this patch only introduces new comments, I'll commit it for now to also test phabricator's commit processing.

include/clang/Tooling/Core/Replacement.h

public:
   /// in either order produces the same result. Note that the range of the
   /// replacement that is applied later still refers to the original code.
   /// These include (but not restricted to) replacements that:
   ///   - don't overlap (being directly adjacent is fine) and
   ///   - are overlapping deletions.
   ///   - are insertions at the same offset and applying them in either order
   ///     has the same effect, i.e. X + Y = Y + X when inserting X and Y
   ///     respectively.
+  ///   - are identical replacements, i.e. applying the same replacement twice
+  ///     is equivalent to applying it once.
   /// Examples:
   /// 1. Replacement A(0, 0, "a") and B(0, 0, "aa") are order-independent since
   ///    applying them in either order gives replacement (0, 0, "aaa").
   ///    However, A(0, 0, "a") and B(0, 0, "b") are order-dependent since
   ///    applying A first gives (0, 0, "ab") while applying B first gives (B, A,
   ///    "ba").
   /// 2. Replacement A(0, 2, "123") and B(0, 2, "123") are order-independent
   ///    since applying them in either order gives (0, 2, "123").
   /// 3. Replacement A(0, 3, "123") and B(2, 3, "321") are order-independent
   ///    since either order gives (0, 5, "12321").
+  /// 4. Replacement A(0, 3, "ab") and B(0, 3, "ab") are order-independent since
+  ///    applying the same replacement twice is equivalent to applying it once.
   /// Replacements with offset UINT_MAX are special - we do not detect conflicts
   /// for such replacements since users may add them intentionally as a special
   /// category of replacements.
   llvm::Error add(const Replacement &R);
 
   /// \brief Merges \p Replaces into the current replacements. \p Replaces
   /// refers to code after applying the current replacements.
   Replacements merge(const Replacements &Replaces) const;