message: Replace ints with size_t at Kythe AnchorRange
diff: @@ -34,10 +34,10 @@ namespace kythe {
  // Anchor's content in the original string (as Anchor is owning its content --
  // string_view is not applicable).
  struct AnchorRange {
  - const int begin;
  - const int length;
  + const size_t begin;
  + const size_t length;
  - AnchorRange(int b, int l) : begin(b), length(l) {}
  + AnchorRange(size_t b, size_t l) : begin(b), length(l) {}
  };
  // Anchor class represents the location and value of some token.
  @@ -45,7 +45,7 @@ class Anchor {
  public:
  explicit Anchor(absl::string_view value) : content_(value) {}
  - explicit Anchor(absl::string_view value, int begin, int length)
  + explicit Anchor(absl::string_view value, size_t begin, size_t length)
  : content_(value) {
  source_text_offset_.emplace(begin, length);
  }
  @@ -74,10 +74,10 @@ class Anchor {
  absl::string_view Text() const { return content_; }
  // Returns the location of the Anchor's content in the original string.
  - int StartLocation() const { return source_text_offset_->begin; }
  + size_t StartLocation() const { return source_text_offset_->begin; }
  // Returns the size of the Anchor's content.
  - int ContentLength() const { return source_text_offset_->length; }
  + size_t ContentLength() const { return source_text_offset_->length; }
  bool operator==(const Anchor&) const;
  bool operator!=(const Anchor& other) const { return !(*this == other); }
  