Bump to WebRTC M120 release

Some API deprecation -- ExperimentalAgc and ExperimentalNs are gone.
We're continuing to carry iSAC even though it's gone upstream, but maybe
we'll want to drop that soon.

webrtc/rtc_base/memory/BUILD.gn

@@ -21,24 +21,22 @@ rtc_library("aligned_malloc") {
 }
 
 # Test only utility.
-# TODO: Tag with `testonly = true` once all depending targets are correctly
-# tagged.
 rtc_library("fifo_buffer") {
+  testonly = true
   visibility = [
     ":unittests",
     "..:rtc_base_tests_utils",
     "..:rtc_base_unittests",
-    "../../p2p:rtc_p2p",  # This needs to be fixed.
   ]
   sources = [
     "fifo_buffer.cc",
     "fifo_buffer.h",
   ]
   deps = [
-    "..:rtc_base",
+    "..:stream",
+    "..:threading",
+    "../../api/task_queue:pending_task_safety_flag",
     "../synchronization:mutex",
-    "../task_utils:pending_task_safety_flag",
-    "../task_utils:to_queued_task",
   ]
 }
 
@@ -46,11 +44,18 @@ rtc_library("unittests") {
   testonly = true
   sources = [
     "aligned_malloc_unittest.cc",
+    "always_valid_pointer_unittest.cc",
     "fifo_buffer_unittest.cc",
   ]
   deps = [
     ":aligned_malloc",
+    ":always_valid_pointer",
     ":fifo_buffer",
     "../../test:test_support",
   ]
 }
+
+rtc_source_set("always_valid_pointer") {
+  sources = [ "always_valid_pointer.h" ]
+  deps = [ "..:checks" ]
+}

webrtc/rtc_base/memory/aligned_malloc.cc

@@ -26,7 +26,7 @@
 namespace webrtc {
 
 uintptr_t GetRightAlign(uintptr_t start_pos, size_t alignment) {
-  // The pointer should be aligned with |alignment| bytes. The - 1 guarantees
+  // The pointer should be aligned with `alignment` bytes. The - 1 guarantees
   // that it is aligned towards the closest higher (right) address.
   return (start_pos + alignment - 1) & ~(alignment - 1);
 }

webrtc/rtc_base/memory/aligned_malloc.h

@@ -21,13 +21,13 @@
 
 namespace webrtc {
 
-// Returns a pointer to the first boundry of |alignment| bytes following the
-// address of |ptr|.
+// Returns a pointer to the first boundry of `alignment` bytes following the
+// address of `ptr`.
 // Note that there is no guarantee that the memory in question is available.
-// |ptr| has no requirements other than it can't be NULL.
+// `ptr` has no requirements other than it can't be NULL.
 void* GetRightAlign(const void* ptr, size_t alignment);
 
-// Allocates memory of |size| bytes aligned on an |alignment| boundry.
+// Allocates memory of `size` bytes aligned on an `alignment` boundry.
 // The return value is a pointer to the memory. Note that the memory must
 // be de-allocated using AlignedFree.
 void* AlignedMalloc(size_t size, size_t alignment);