Some tiny fixes:

- Fix the bug that when command line is too large
- Add weak symbol annotation to RunOnValgrind to avoid conflicts with absel

src/butil/process_util.cc

@@ -59,8 +59,7 @@ ssize_t ReadCommandLine(char* buf, size_t len, bool with_args) {
 
     if (with_args) {
         if ((size_t)nr == len) {
-            LOG(ERROR) << "buf is not big enough";
-            return -1;
+            return len;
         }
         for (ssize_t i = 0; i < nr; ++i) {
             if (buf[i] == '\0') {

src/butil/third_party/dynamic_annotations/dynamic_annotations.c

@@ -255,7 +255,7 @@ static int GetRunningOnValgrind(void) {
 }
 
 /* See the comments in dynamic_annotations.h */
-int RunningOnValgrind(void) {
+int DYNAMIC_ANNOTATIONS_ATTRIBUTE_WEAK RunningOnValgrind(void) {
   static volatile int running_on_valgrind = -1;
   /* C doesn't have thread-safe initialization of statics, and we
      don't want to depend on pthread_once here, so hack it. */