Buildsystem: Improve detect.py readability and fix issues

Tried to organize the configure(env) calls in sections, using the same order
for all platforms whenever possible.

Apart from cosmetic changes, the following issues were fixed:
- Android: cleanup linkage, remove GLESv1_CM and GLESv2
- iPhone: Remove obsolete "ios_gles22_override" option
- OSX:
  * Fix bits detection (default to 64) and remove obsolete "force_64_bits" option
    (closes #9449)
  * Make "fat" bits argument explicit
- Server: sync with X11
- Windows: clean up old DirectX 9 stuff
- X11:
  * Do not require system OpenSSL for building (closes #9443)
  * Fix typo'ed use_leak_sanitizer option
  * Fix .llvm suffix overriding custom extra_suffix

platform/javascript/detect.py

@@ -1,6 +1,6 @@
 import os
-import sys
 import string
+import sys
 
 
 def is_active():
@@ -12,7 +12,8 @@ def get_name():
 
 
 def can_build():
-    return os.environ.has_key("EMSCRIPTEN_ROOT")
+
+    return (os.environ.has_key("EMSCRIPTEN_ROOT"))
 
 
 def get_opts():
@@ -27,12 +28,12 @@ def get_flags():
 
     return [
         ('tools', 'no'),
-        ('module_etc1_enabled', 'no'),
         ('module_theora_enabled', 'no'),
     ]
 
 
 def create(env):
+
     # remove Windows' .exe suffix
     return env.Clone(tools=['textfile', 'zip'], PROGSUFFIX='')
 
@@ -45,10 +46,26 @@ def escape_target_backslashes(target, source, env, for_signature):
 
 
 def configure(env):
+
+    ## Build type
+
+    if (env["target"] == "release"):
+        env.Append(CCFLAGS=['-O3'])
+        env.Append(LINKFLAGS=['-O3'])
+
+    elif (env["target"] == "release_debug"):
+        env.Append(CCFLAGS=['-O2', '-DDEBUG_ENABLED'])
+        env.Append(LINKFLAGS=['-O2', '-s', 'ASSERTIONS=1'])
+        # retain function names at the cost of file size, for backtraces and profiling
+        env.Append(LINKFLAGS=['--profiling-funcs'])
+
+    elif (env["target"] == "debug"):
+        env.Append(CCFLAGS=['-O1', '-D_DEBUG', '-g', '-DDEBUG_ENABLED'])
+        env.Append(LINKFLAGS=['-O1', '-g'])
+
+    ## Compiler configuration
+
     env['ENV'] = os.environ
-
-    env.Append(CPPPATH=['#platform/javascript'])
-
     env.PrependENVPath('PATH', os.environ['EMSCRIPTEN_ROOT'])
     env['CC']      = 'emcc'
     env['CXX']     = 'em++'
@@ -57,6 +74,7 @@ def configure(env):
     # Emscripten's ar has issues with duplicate file names, so use cc
     env['AR']      = 'emcc'
     env['ARFLAGS'] = '-o'
+
     if (os.name == 'nt'):
         # use TempFileMunge on Windows since some commands get too long for
         # cmd.exe even with spawn_fix
@@ -68,26 +86,20 @@ def configure(env):
     env['OBJSUFFIX'] = '.bc'
     env['LIBSUFFIX'] = '.bc'
 
-    if (env["target"] == "release"):
-        env.Append(CCFLAGS=['-O3'])
-        env.Append(LINKFLAGS=['-O3'])
-    elif (env["target"] == "release_debug"):
-        env.Append(CCFLAGS=['-O2', '-DDEBUG_ENABLED'])
-        env.Append(LINKFLAGS=['-O2', '-s', 'ASSERTIONS=1'])
-        # retain function names at the cost of file size, for backtraces and profiling
-        env.Append(LINKFLAGS=['--profiling-funcs'])
-    elif (env["target"] == "debug"):
-        env.Append(CCFLAGS=['-O1', '-D_DEBUG', '-g', '-DDEBUG_ENABLED'])
-        env.Append(LINKFLAGS=['-O1', '-g'])
+    ## Compile flags
 
-    # TODO: Move that to opus module's config
-    if("module_opus_enabled" in env and env["module_opus_enabled"] != "no"):
-        env.opus_fixed_point = "yes"
+    env.Append(CPPPATH=['#platform/javascript'])
+    env.Append(CPPFLAGS=['-DJAVASCRIPT_ENABLED', '-DUNIX_ENABLED', '-DPTHREAD_NO_RENAME', '-DTYPED_METHOD_BIND', '-DNO_THREADS'])
+    env.Append(CPPFLAGS=['-DGLES3_ENABLED'])
 
     # These flags help keep the file size down
     env.Append(CPPFLAGS=["-fno-exceptions", '-DNO_SAFE_CAST', '-fno-rtti'])
-    env.Append(CPPFLAGS=['-DJAVASCRIPT_ENABLED', '-DUNIX_ENABLED', '-DPTHREAD_NO_RENAME', '-DTYPED_METHOD_BIND', '-DNO_THREADS'])
-    env.Append(CPPFLAGS=['-DGLES3_ENABLED'])
+
+    if env['javascript_eval'] == 'yes':
+        env.Append(CPPFLAGS=['-DJAVASCRIPT_EVAL_ENABLED'])
+
+    ## Link flags
+
     env.Append(LINKFLAGS=['-s', 'USE_WEBGL2=1'])
 
     if (env['wasm'] == 'yes'):
@@ -101,8 +113,6 @@ def configure(env):
         env.Append(LINKFLAGS=['-s', 'ASM_JS=1'])
         env.Append(LINKFLAGS=['--separate-asm'])
 
-    if env['javascript_eval'] == 'yes':
-        env.Append(CPPFLAGS=['-DJAVASCRIPT_EVAL_ENABLED'])
-
-
-    import methods
+    # TODO: Move that to opus module's config
+    if("module_opus_enabled" in env and env["module_opus_enabled"] != "no"):
+        env.opus_fixed_point = "yes"