Fix "unsafe narrowing" warnings in absl, 4/n.

Addresses failures with the following, in some files:
-Wshorten-64-to-32
-Wimplicit-int-conversion
-Wsign-compare
-Wsign-conversion
-Wtautological-unsigned-zero-compare

(This specific CL focuses on .cc files in strings/, except /internal/.)

Bug: chromium:1292951
PiperOrigin-RevId: 465285043
Change-Id: I37e9d1b4c4e9aa655b720da1467927af2aba995e

1 files changed, 6 insertions, 2 deletions

diff --git a/absl/strings/cord_buffer.h b/absl/strings/cord_buffer.h
index 09a74ad5..15494b31 100644
--- a/absl/strings/cord_buffer.h
+++ b/absl/strings/cord_buffer.h
@@ -411,8 +411,12 @@ class CordBuffer {
 
   // Power2 functions
   static bool IsPow2(size_t size) { return absl::has_single_bit(size); }
-  static size_t Log2Floor(size_t size) { return absl::bit_width(size) - 1; }
-  static size_t Log2Ceil(size_t size) { return absl::bit_width(size - 1); }
+  static size_t Log2Floor(size_t size) {
+    return static_cast<size_t>(absl::bit_width(size) - 1);
+  }
+  static size_t Log2Ceil(size_t size) {
+    return static_cast<size_t>(absl::bit_width(size - 1));
+  }
 
   // Implementation of `CreateWithCustomLimit()`.
   // This implementation allows for future memory allocation hints to