node: update to v12.18.4

Vulnerabilities fixed:
* CVE-2020-8201: HTTP Request Smuggling due to CR-to-Hyphen conversion (High).
* CVE-2020-8252: fs.realpath.native on may cause buffer overflow (Medium).

Imported patches from the debian package.

Signed-off-by: Hirokazu MORIKAWA <morikw2@gmail.com>

lang/node/patches/999-mips-less-memory.patch

@@ -0,0 +1,26 @@
+Description: mksnapshot uses too much memory on 32-bit mipsel
+Author: Jérémy Lal <kapouer@melix.org>
+Last-Update: 2020-06-03
+Forwarded: https://bugs.chromium.org/p/v8/issues/detail?id=10586
+--- a/deps/v8/src/common/globals.h
++++ b/deps/v8/src/common/globals.h
+@@ -206,7 +206,7 @@
+ constexpr size_t kMinExpectedOSPageSize = 64 * KB;  // OS page on PPC Linux
+ #elif V8_TARGET_ARCH_MIPS
+ constexpr bool kRequiresCodeRange = false;
+-constexpr size_t kMaximalCodeRangeSize = 2048LL * MB;
++constexpr size_t kMaximalCodeRangeSize = 512 * MB;
+ constexpr size_t kMinimumCodeRangeSize = 0 * MB;
+ constexpr size_t kMinExpectedOSPageSize = 4 * KB;  // OS page.
+ #else
+--- a/deps/v8/src/codegen/mips/constants-mips.h
++++ b/deps/v8/src/codegen/mips/constants-mips.h
+@@ -137,7 +137,7 @@
+ namespace v8 {
+ namespace internal {
+ 
+-constexpr size_t kMaxPCRelativeCodeRangeInMB = 4096;
++constexpr size_t kMaxPCRelativeCodeRangeInMB = 1024;
+ 
+ // -----------------------------------------------------------------------------
+ // Registers and FPURegisters.