[sql] uClibc doesn't provide malloc_usable_size().

third_party/sqlite/BUILD.gn

Index: third_party/sqlite/BUILD.gn
diff --git a/third_party/sqlite/BUILD.gn b/third_party/sqlite/BUILD.gn
index 76b92153f2292eeacdcfb864fe074e35af5c05c7..395bfa5750f68f323ef952d7792cb591e68c7e22 100644
--- a/third_party/sqlite/BUILD.gn
+++ b/third_party/sqlite/BUILD.gn
@@ -36,6 +36,7 @@ if (!use_system_sqlite) {
     visibility = [ ":*" ]
 
     sources = [
+      "amalgamation/config.h",
       "amalgamation/sqlite3.c",
       "amalgamation/sqlite3.h",
     ]
@@ -122,15 +123,10 @@ if (!use_system_sqlite) {
       ]
     }
 
-    # SQLite wants to track malloc sizes.  On OSX it uses malloc_size(), on
-    # Windows _msize(), elsewhere it handles it manually by enlarging the malloc
-    # and injecting a field.  Enable malloc_usable_size() for Linux.
-    # NOTE(shess): Android does _not_ export malloc_usable_size().
+    # Pull in config.h on Linux.  This allows use of preprocessor macros which
+    # are not available to the build config.
     if (is_linux) {
-      defines += [
-        "HAVE_MALLOC_H",
-        "HAVE_MALLOC_USABLE_SIZE",
-      ]
+      defines += [ "_HAVE_SQLITE_CONFIG_H" ]
     }
 
     include_dirs = [ "amalgamation" ]