Add v8_os_page_size flag for cross compilation

src/flag-definitions.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file defines all of the flags.  It is separated into different section,
 // for Debug, Release, Logging and Profiling, etc.  To add a new flag, find the
 // correct section, and use one of the DEFINE_ macros, without a trailing ';'.
 //
 // This include does not have a guard, because it is a template-style include,
 // which can be included multiple times in different modes.  It expects to have
@@ skipping 749 matching lines @@
             "trace native contexts that are expected to be garbage collected")
 DEFINE_IMPLICATION(trace_detached_contexts, track_detached_contexts)
 #ifdef VERIFY_HEAP
 DEFINE_BOOL(verify_heap, false, "verify heap pointers before and after GC")
 #endif
 DEFINE_BOOL(move_object_start, true, "enable moving of object starts")
 DEFINE_BOOL(memory_reducer, true, "use memory reducer")
 DEFINE_INT(heap_growing_percent, 0,
            "specifies heap growing factor as (1 + heap_growing_percent/100)")
 
+// spaces.cc
+DEFINE_INT(v8_os_page_size, 0, "override OS page size (in KBytes)")
+
 // execution.cc, messages.cc
 DEFINE_BOOL(clear_exceptions_on_js_entry, false,
             "clear pending exceptions when entering JavaScript")
 
 // counters.cc
 DEFINE_INT(histogram_interval, 600000,
            "time interval in ms for aggregating memory histograms")
 
 // global-handles.cc
 DEFINE_BOOL(trace_object_groups, false,
@@ skipping 232 matching lines @@
 
 // runtime.cc
 DEFINE_BOOL(trace_lazy, false, "trace lazy compilation")
 
 // spaces.cc
 DEFINE_BOOL(collect_heap_spill_statistics, false,
             "report heap spill statistics along with heap_stats "
             "(requires heap_stats)")
 DEFINE_BOOL(trace_live_bytes, false,
             "trace incrementing and resetting of live bytes")
-
 DEFINE_BOOL(trace_isolates, false, "trace isolate state changes")
 
 // Regexp
 DEFINE_BOOL(regexp_possessive_quantifier, false,
             "enable possessive quantifier syntax for testing")
 DEFINE_BOOL(trace_regexp_bytecodes, false, "trace regexp bytecode execution")
 DEFINE_BOOL(trace_regexp_assembler, false,
             "trace regexp macro assembler calls.")
 DEFINE_BOOL(trace_regexp_parser, false, "trace regexp parsing")
 
@@ skipping 194 matching lines @@
 #undef DEFINE_ALIAS_FLOAT
 #undef DEFINE_ALIAS_ARGS
 
 #undef FLAG_MODE_DECLARE
 #undef FLAG_MODE_DEFINE
 #undef FLAG_MODE_DEFINE_DEFAULTS
 #undef FLAG_MODE_META
 #undef FLAG_MODE_DEFINE_IMPLICATIONS
 
 #undef COMMA