Everywhere: Rename {Deprecated => Byte}String

This commit un-deprecates DeprecatedString, and repurposes it as a byte
string.
As the null state has already been removed, there are no other
particularly hairy blockers in repurposing this type as a byte string
(what it _really_ is).

This commit is auto-generated:
  $ xs=$(ack -l \bDeprecatedString\b\|deprecated_string AK Userland \
    Meta Ports Ladybird Tests Kernel)
  $ perl -pie 's/\bDeprecatedString\b/ByteString/g;
    s/deprecated_string/byte_string/g' $xs
  $ clang-format --style=file -i \
    $(git diff --name-only | grep \.cpp\|\.h)
  $ gn format $(git ls-files '*.gn' '*.gni')

Userland/DevTools/Profiler/Profile.h

@@ -35,7 +35,7 @@ extern OwnPtr<Debug::DebugInfo> g_kernel_debug_info;
 
 class ProfileNode : public RefCounted<ProfileNode> {
 public:
-    static NonnullRefPtr<ProfileNode> create(Process const& process, DeprecatedFlyString const& object_name, DeprecatedString symbol, FlatPtr address, u32 offset, u64 timestamp, pid_t pid)
+    static NonnullRefPtr<ProfileNode> create(Process const& process, DeprecatedFlyString const& object_name, ByteString symbol, FlatPtr address, u32 offset, u64 timestamp, pid_t pid)
     {
         return adopt_ref(*new ProfileNode(process, object_name, move(symbol), address, offset, timestamp, pid));
     }
@@ -55,7 +55,7 @@ public:
     void did_see_event(size_t event_index) { m_seen_events.set(event_index, true); }
 
     DeprecatedFlyString const& object_name() const { return m_object_name; }
-    DeprecatedString const& symbol() const { return m_symbol; }
+    ByteString const& symbol() const { return m_symbol; }
     FlatPtr address() const { return m_address; }
     u32 offset() const { return m_offset; }
     u64 timestamp() const { return m_timestamp; }
@@ -75,7 +75,7 @@ public:
         m_children.append(child);
     }
 
-    ProfileNode& find_or_create_child(DeprecatedFlyString const& object_name, DeprecatedString symbol, FlatPtr address, u32 offset, u64 timestamp, pid_t pid)
+    ProfileNode& find_or_create_child(DeprecatedFlyString const& object_name, ByteString symbol, FlatPtr address, u32 offset, u64 timestamp, pid_t pid)
     {
         for (size_t i = 0; i < m_children.size(); ++i) {
             auto& child = m_children[i];
@@ -113,13 +113,13 @@ public:
 
 private:
     explicit ProfileNode(Process const&);
-    explicit ProfileNode(Process const&, DeprecatedFlyString const& object_name, DeprecatedString symbol, FlatPtr address, u32 offset, u64 timestamp, pid_t);
+    explicit ProfileNode(Process const&, DeprecatedFlyString const& object_name, ByteString symbol, FlatPtr address, u32 offset, u64 timestamp, pid_t);
 
     bool m_root { false };
     Process const& m_process;
     ProfileNode* m_parent { nullptr };
     DeprecatedFlyString m_object_name;
-    DeprecatedString m_symbol;
+    ByteString m_symbol;
     pid_t m_pid { 0 };
     FlatPtr m_address { 0 };
     u32 m_offset { 0 };
@@ -168,7 +168,7 @@ public:
 
     struct Frame {
         DeprecatedFlyString object_name;
-        DeprecatedString symbol;
+        ByteString symbol;
         FlatPtr address { 0 };
         u32 offset { 0 };
     };
@@ -196,14 +196,14 @@ public:
         };
 
         struct SignpostData {
-            DeprecatedString string;
+            ByteString string;
             FlatPtr arg {};
         };
 
         struct MmapData {
             FlatPtr ptr {};
             size_t size {};
-            DeprecatedString name;
+            ByteString name;
         };
 
         struct MunmapData {
@@ -213,11 +213,11 @@ public:
 
         struct ProcessCreateData {
             pid_t parent_pid { 0 };
-            DeprecatedString executable;
+            ByteString executable;
         };
 
         struct ProcessExecData {
-            DeprecatedString executable;
+            ByteString executable;
         };
 
         struct ThreadCreateData {
@@ -227,31 +227,31 @@ public:
         // Based on Syscall::SC_open_params
         struct OpenEventData {
             int dirfd;
-            DeprecatedString path;
+            ByteString path;
             int options;
             u64 mode;
         };
 
         struct CloseEventData {
             int fd;
-            DeprecatedString path;
+            ByteString path;
         };
 
         struct ReadvEventData {
             int fd;
-            DeprecatedString path;
+            ByteString path;
             // struct iovec* iov; // TODO: Implement
             // int iov_count; // TODO: Implement
         };
 
         struct ReadEventData {
             int fd;
-            DeprecatedString path;
+            ByteString path;
         };
 
         struct PreadEventData {
             int fd;
-            DeprecatedString path;
+            ByteString path;
             FlatPtr buffer_ptr;
             size_t size;
             off_t offset;