Changes imported from Abseil "staging" branch:

- b7ac57541b07fadc3ed054cc3d62bc192a2098a7 Redefine arithmetic assign operators in terms of the bina... by Alex Strelnikov <strel@google.com>
  - bb2bf3fd86eb9f24420376aad1b9fe84068ad7e4 Cmake CI for Ubuntu by Jon Cohen <cohenjon@google.com>
  - 3ff3e6d6b4d99627f0785cad5b562362bdf1ae37 Fix internal namespace (debug_internal -> debugging_inter... by Derek Mauro <dmauro@google.com>
  - b50753d757c95a3430cc2d6cfc0272af1e5c219c Internal change. by Alex Strelnikov <strel@google.com>

GitOrigin-RevId: b7ac57541b07fadc3ed054cc3d62bc192a2098a7
Change-Id: I7561639e296d1cc5dc7ee75e6645e8dae3f1bf97

absl/debugging/internal/elf_mem_image.h

@@ -39,7 +39,7 @@
 #include <link.h>  // for ElfW
 
 namespace absl {
-namespace debug_internal {
+namespace debugging_internal {
 
 // An in-memory ELF image (may not exist on disk).
 class ElfMemImage {
@@ -122,7 +122,7 @@ class ElfMemImage {
   ElfW(Addr) link_base_;     // Link-time base (p_vaddr of first PT_LOAD).
 };
 
-}  // namespace debug_internal
+}  // namespace debugging_internal
 }  // namespace absl
 
 #endif  // ABSL_HAVE_ELF_MEM_IMAGE