Remove unnecessary intermediate casts in CodedOutputStream

https://docs.oracle.com/javase/specs/jls/se10/html/jls-5.html#jls-5.1.3

The JLS guarantees this is the same:

> A narrowing conversion of a signed integer to an integral type T simply discards all but the n lowest order bits, where n is the number of bits used to represent type T. In addition to a possible loss of information about the magnitude of the numeric value, this may cause the sign of the resulting value to differ from the sign of the input value.

PiperOrigin-RevId: 683416604

java/core/src/main/java/com/google/protobuf/CodedOutputStream.java

@@ -1414,14 +1414,14 @@ public abstract class CodedOutputStream extends ByteOutput {
     public final void writeFixed64NoTag(long value) throws IOException {
       int position = this.position; // Perf: hoist field to register to avoid load/stores.
       try {
-        buffer[position] = (byte) ((int) value);
-        buffer[position + 1] = (byte) ((int) (value >> 8));
-        buffer[position + 2] = (byte) ((int) (value >> 16));
-        buffer[position + 3] = (byte) ((int) (value >> 24));
-        buffer[position + 4] = (byte) ((int) (value >> 32));
-        buffer[position + 5] = (byte) ((int) (value >> 40));
-        buffer[position + 6] = (byte) ((int) (value >> 48));
-        buffer[position + 7] = (byte) ((int) (value >> 56));
+        buffer[position] = (byte) value;
+        buffer[position + 1] = (byte) (value >> 8);
+        buffer[position + 2] = (byte) (value >> 16);
+        buffer[position + 3] = (byte) (value >> 24);
+        buffer[position + 4] = (byte) (value >> 32);
+        buffer[position + 5] = (byte) (value >> 40);
+        buffer[position + 6] = (byte) (value >> 48);
+        buffer[position + 7] = (byte) (value >> 56);
       } catch (IndexOutOfBoundsException e) {
         throw new OutOfSpaceException(position, limit, FIXED64_SIZE, e);
       }
@@ -2384,10 +2384,10 @@ public abstract class CodedOutputStream extends ByteOutput {
       buffer[position++] = (byte) (value >> 8);
       buffer[position++] = (byte) (value >> 16);
       buffer[position++] = (byte) (value >> 24);
-      buffer[position++] = (byte) ((int) (value >> 32));
-      buffer[position++] = (byte) ((int) (value >> 40));
-      buffer[position++] = (byte) ((int) (value >> 48));
-      buffer[position++] = (byte) ((int) (value >> 56));
+      buffer[position++] = (byte) (value >> 32);
+      buffer[position++] = (byte) (value >> 40);
+      buffer[position++] = (byte) (value >> 48);
+      buffer[position++] = (byte) (value >> 56);
       this.position = position;
       totalBytesWritten += FIXED64_SIZE;
     }