Allows building debian packages for ARM.

tools/linux_dist_support/debian/rules

 #!/usr/bin/make -f
 export DH_VERBOSE = 1
 
 # Use DEB_BUILD_OPTIONS's parallel=n option (see Policy 4.9.1)
 ifneq (,$(findstring parallel,$(DEB_BUILD_OPTIONS)))
 PARALLEL_JOBS := $(shell echo $(DEB_BUILD_OPTIONS) | \
         sed -e 's/.*parallel=\([0-9]\+\).*/\1/')
 else
 PARALLEL_JOBS := 1
 endif
 
-DEB_HOST_ARCH_CPU := $(shell dpkg-architecture -qDEB_HOST_ARCH_CPU)
 ifeq (amd64,$(DEB_HOST_ARCH_CPU))
 BUILD_TYPE += ReleaseX64
+ARCH += x64
 else
 ifeq (i386,$(DEB_HOST_ARCH_CPU))
 BUILD_TYPE += ReleaseIA32
+ARCH += ia32
 else
-$(warning unsupported target arch $(DEB_HOST_ARCH_CPU) - continuing anyway)
+ifeq (arm,$(DEB_HOST_ARCH_CPU))
+ifeq ($(DEB_BUILD_ARCH_CPU),$(DEB_HOST_ARCH_CPU))
+BUILD_TYPE += ReleaseARM
+else
+BUILD_TYPE += ReleaseXARM
+endif
+ARCH += arm
+else
+$(error unsupported target arch '$(DEB_HOST_ARCH_CPU)')
+endif
 endif
 endif
 
 # Verbose?
 ifeq (1,$(DH_VERBOSE))
 BUILD_ARGS += V=1
 endif
 
 %:
         dh $@
 
 override_dh_auto_clean:
         echo $(DEB_BUILD_OPTIONS)
         rm -fr dart/out dart/Makefile
         find . -name *.tmp -execdir rm -f {} \;
         find . -name *.pyc -execdir rm -f {} \;
         find . -name *.mk -execdir rm -f {} \;
         find . -name *.Makefile -execdir rm -f {} \;
 
 override_dh_auto_configure:
         GYP_GENERATORS=make python dart/tools/gyp_dart.py all
 
 override_dh_auto_build:
-        make -C dart -j$(PARALLEL_JOBS) \
-                BUILDTYPE=$(BUILD_TYPE) $(BUILD_ARGS) create_sdk
+        cd dart; \
+        python tools/build.py -v -m release -a $(ARCH) $(TOOLCHAIN) create_sdk; \
+        cd ..
 
 # Building the Dart SDK will already strip all binaries.
 override_dh_strip:
 
+# This override allows us to ignore spurious missing library errors when
+# cross-compiling.
+override_dh_shlibdeps:
+        dh_shlibdeps --dpkg-shlibdeps-params=--ignore-missing-info
+
 override_dh_auto_install:
         mkdir -p debian/tmp/out
         cp -R dart/out/$(BUILD_TYPE)/dart-sdk debian/tmp/out
         mv debian/tmp/out/dart-sdk debian/tmp/out/dart
         dh_install
         dh_link