IDL: Drop value conversion (V8 -> C++) macros from generated code

Source/bindings/core/v8/V8BindingMacros.h

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@@ skipping 15 matching lines @@
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 #ifndef V8BindingMacros_h
 #define V8BindingMacros_h
 
 namespace blink {
 
+#define TONATIVE_CONVERT(expression, bailout) \
+    if (!(expression))                        \
+        bailout;                              \
+
+#define TONATIVE_DECLARE(type, var, expression, bailout) \

[yhirano, 2015/02/24 03:51:24]

[optional] This is not a strong opinion, but I don't see a strong benefit of
this macro: In most (if not all) of occurrences, |expression| contains the
variable name (e.g. TONATIVE_DECLARE(V8StringResource<>, cppValue, (cppValue =
v8Value).prepare(exceptionState), return false)).

It doesn't save symbols from manual declaration with TONATIVE_CONVERT (e.g.
V8Stringresource<> cppValue; TONATIVE_CONVERT((cppValue =
v8Value).prepare(exceptionState), return false)). I feel the latter easier to
read.

[Jens Widell, 2015/02/24 07:31:43]

Essentially, I don't see a strong benefit to either of these macros. They are
effectively only here so that the Python scripts can provide single-line
"expression-like" code snippets for the Jinja templates to use.

If we were okay with the Python scripts generating (simple) multi-line code
snippets for the Jinja templates to use, we can easily get rid fo these macros
entirely.

+    type var;                                            \
+    TONATIVE_CONVERT(expression, bailout)
+
 // Naming scheme:
 // TO*_RETURNTYPE[_ARGTYPE]...
 // ...using _DEFAULT instead of _ANY..._ANY when returing a default value.
 
 #define TONATIVE_EXCEPTION(type, var, value) \
     type var;                                \
     {                                        \
         v8::TryCatch block;                  \
         var = (value);                       \
         if (UNLIKELY(block.HasCaught()))     \
@@ skipping 104 matching lines @@
 #define TOSTRING_VOID_EXCEPTIONSTATE_PROMISE_INTERNAL(var, value, exceptionState, info, scriptState) \
     var = (value);                                                                                   \
     if (UNLIKELY(!var.prepare(exceptionState)))  {                                                   \
         v8SetReturnValue(info, exceptionState.reject(scriptState).v8Value());                        \
         return;                                                                                      \
     }
 
 } // namespace blink
 
 #endif // V8BindingMacros_h