Update to clang-4053586.

This has been outdated for quite some time. Upgrade to the current
platform and NDK toolchain that is in use.

Test: android/ndk#399
Change-Id: I64b4fe2032546e584191261b6f46b2deafb3ea27

build/tools/builder-funcs.sh

@@ -591,11 +591,9 @@ builder_begin_android ()
         esac
         SCRATCH_FLAGS="-target $LLVM_TRIPLE $FLAGS"
         builder_ldflags "$SCRATCH_FLAGS"
-        if [ "$LLVM_VERSION" \> "3.4" ]; then
-            # Turn off integrated-as for clang >= 3.5 due to ill-formed object it produces
-            # involving inline-assembly .pushsection/.popsection which crashes ld.gold
-            # BUG=18589643
-            SCRATCH_FLAGS="$SCRATCH_FLAGS -fno-integrated-as"
+        if [ "$ABI" == "mips64" ]; then
+            # https://github.com/android-ndk/ndk/issues/399
+            SCRATCH_FLAGS="$SCRATCH_FLAGS -fintegrated-as"
         fi
         builder_cflags  "$SCRATCH_FLAGS"
         builder_cxxflags "$SCRATCH_FLAGS"

build/tools/prebuilt-common.sh

@@ -1293,7 +1293,7 @@ get_llvm_toolchain_binprefix ()
 {
     local NAME DIR BINPREFIX
     local SYSTEM=${1:-$(get_prebuilt_host_tag)}
-    local VERSION=2812033
+    local VERSION=4053586
     SYSTEM=${SYSTEM%_64} # Trim _64 suffix. We only have one LLVM.
     BINPREFIX=$ANDROID_BUILD_TOP/prebuilts/clang/host/$SYSTEM/clang-$VERSION/bin
     echo "$BINPREFIX"