Restrict Termux engine builds to aarch64 only (#6)

* Initial plan

* fix: restrict termux builds to aarch64

Co-authored-by: GeneralKaos666 <161671171+GeneralKaos666@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: GeneralKaos666 <161671171+GeneralKaos666@users.noreply.github.com>

Author: Copilot

build.py

@@ -56,7 +56,13 @@ def __init__(self, conf='build.toml'):
         # TODO: detect host
         self.host = 'linux-x86_64'
         self.repo = repo or 'https://github.com/flutter/flutter'
-        self.arch = arch or 'arm64'
+        if not arch:
+            arch = ['arm64']
+        elif isinstance(arch, str):
+            arch = [arch]
+        if any(utils.termux_arch(it) != 'aarch64' for it in arch):
+            raise ValueError('only arm64/aarch64 Termux builds are supported')
+        self.arch = arch
         self.mode = mode or 'debug'
         self.sysroot = Sysroot(path=path/syspath, **sysroot)
         self.root = path/root
@@ -162,6 +168,7 @@ def configure(
             '--gn-args', 'is_termux=true',
             '--gn-args', f'is_termux_host={utils.__TERMUX__}',
             '--gn-args', f'termux_api_level={api}',
+            '--gn-args', f'termux_enabled_archs=["{arch}"]',
             '--gn-args', 'extra_ldflags=["-lEGL", "-lGLESv2"]',
 			'--gn-args', f'extra_cflags_cc=["-I{toolchain}/../../../sources/third_party/vulkan/include"]',
         ]

patches/engine.patch

@@ -376,20 +376,21 @@ new file mode 100644
 index 0000000..0d97976
 --- /dev/null
 +++ b/engine/src/build/config/termux/termux.gni
-@@ -0,0 +1,6 @@
+@@ -0,0 +1,7 @@
 +declare_args() {
 +  termux_api_level = 26
 +
 +  is_termux = false
 +  is_termux_host = false
++  termux_enabled_archs = [ "arm64" ]
 +}
 +
 diff --git a/engine/src/build/toolchain/termux/BUILD.gn b/engine/src/build/toolchain/termux/BUILD.gn
 new file mode 100644
-index 0000000..564c582
+index 0000000..6f2f9fd
 --- /dev/null
 +++ b/engine/src/build/toolchain/termux/BUILD.gn
-@@ -0,0 +1,40 @@
+@@ -0,0 +1,34 @@
 +import("//build/toolchain/gcc_toolchain.gni")
 +import("//build/config/android/config.gni")
 +import("//build/config/termux/termux.gni")
@@ -415,23 +416,13 @@ index 0000000..564c582
 +  }
 +}
 +
-+termux_toolchain("arm64"){
-+  toolchain_cpu = "arm64"
-+}
-+
-+termux_toolchain("arm"){
-+  toolchain_cpu = "arm"
-+}
-+
-+termux_toolchain("x64"){
-+  toolchain_cpu = "x64"
-+}
-+
-+termux_toolchain("x86"){
-+  toolchain_cpu = "x86"
++foreach(arch, termux_enabled_archs) {
++  termux_toolchain(arch) {
++    toolchain_cpu = arch
++  }
 +}
 
-   metadata = {
+    metadata = {
 diff --git a/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn b/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn
 --- a/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn
 +++ b/engine/src/flutter/build/secondary/third_party/inja/BUILD.gn