tp: add common_flags, query subcommand, and dispatcher (#5128)

## Summary
- Shared infrastructure: common_flags.h/.cc (GlobalOptions, BuildConfig,
SetupTraceProcessor, LoadTraceFile with symbolization/deobfuscation)
- Query subcommand with -f, -c, -i, -W, -p flags
- ClassicSubcommand: moves entire classic path into a Subcommand, uses
shared infra
- Thin dispatcher: finds subcommand or falls back to classic
- Integration tests for query subcommand and classic backcompat

Part 2/7 of the subcommand CLI implementation (RFC-0018).

## Stack
1. #5134 — SubcommandContext + GetLongOptions() interface
2. **#5128** ← this PR — common_flags + query + ClassicSubcommand +
dispatcher
3. #5129 — repl + serve subcommands
4. #5130 — summarize + export subcommands
5. #5131 — metrics subcommand
6. #5132 — help system + file collision + classic edge case tests
7. #5133 — BUILD.gn consolidation

Author: LalitMaganti

Android.bp

@@ -16811,6 +16811,8 @@ filegroup {
 filegroup {
     name: "perfetto_src_trace_processor_shell_subcommand",
     srcs: [
+        "src/trace_processor/shell/common_flags.cc",
+        "src/trace_processor/shell/query_subcommand.cc",
         "src/trace_processor/shell/subcommand.cc",
     ],
 }
@@ -17154,6 +17156,7 @@ cc_library_static {
         ":perfetto_src_trace_processor_shell_query",
         ":perfetto_src_trace_processor_shell_shell_utils",
         ":perfetto_src_trace_processor_shell_sql_packages",
+        ":perfetto_src_trace_processor_shell_subcommand",
         ":perfetto_src_trace_processor_sorter_sorter",
         ":perfetto_src_trace_processor_sqlite_bindings_bindings",
         ":perfetto_src_trace_processor_sqlite_sqlite",
@@ -19253,6 +19256,7 @@ cc_test {
         ":perfetto_include_perfetto_ext_trace_processor_export_json",
         ":perfetto_include_perfetto_ext_trace_processor_importers_memory_tracker_memory_tracker",
         ":perfetto_include_perfetto_ext_trace_processor_rpc_query_result_serializer",
+        ":perfetto_include_perfetto_ext_trace_processor_trace_processor_shell",
         ":perfetto_include_perfetto_ext_traced_sys_stats_counters",
         ":perfetto_include_perfetto_ext_traced_traced",
         ":perfetto_include_perfetto_ext_tracing_core_core",
@@ -19598,6 +19602,10 @@ cc_test {
         ":perfetto_src_trace_processor_perfetto_sql_tokenizer_unittests",
         ":perfetto_src_trace_processor_rpc_rpc",
         ":perfetto_src_trace_processor_rpc_unittests",
+        ":perfetto_src_trace_processor_shell_metatrace",
+        ":perfetto_src_trace_processor_shell_query",
+        ":perfetto_src_trace_processor_shell_shell_utils",
+        ":perfetto_src_trace_processor_shell_sql_packages",
         ":perfetto_src_trace_processor_shell_subcommand",
         ":perfetto_src_trace_processor_shell_unittests",
         ":perfetto_src_trace_processor_sorter_sorter",
@@ -19642,6 +19650,7 @@ cc_test {
         ":perfetto_src_trace_processor_util_simple_json_serializer",
         ":perfetto_src_trace_processor_util_sql_argument",
         ":perfetto_src_trace_processor_util_stdlib",
+        ":perfetto_src_trace_processor_util_symbolizer_symbolize_database",
         ":perfetto_src_trace_processor_util_symbolizer_symbolizer",
         ":perfetto_src_trace_processor_util_symbolizer_unittests",
         ":perfetto_src_trace_processor_util_tar_writer",

BUILD

@@ -648,6 +648,7 @@ perfetto_cc_library(
         ":src_trace_processor_shell_query",
         ":src_trace_processor_shell_shell_utils",
         ":src_trace_processor_shell_sql_packages",
+        ":src_trace_processor_shell_subcommand",
         ":src_trace_processor_sorter_sorter",
         ":src_trace_processor_sqlite_bindings_bindings",
         ":src_trace_processor_sqlite_sqlite",
@@ -4142,6 +4143,19 @@ perfetto_filegroup(
     ],
 )
 
+# GN target: //src/trace_processor/shell:subcommand
+perfetto_filegroup(
+    name = "src_trace_processor_shell_subcommand",
+    srcs = [
+        "src/trace_processor/shell/common_flags.cc",
+        "src/trace_processor/shell/common_flags.h",
+        "src/trace_processor/shell/query_subcommand.cc",
+        "src/trace_processor/shell/query_subcommand.h",
+        "src/trace_processor/shell/subcommand.cc",
+        "src/trace_processor/shell/subcommand.h",
+    ],
+)
+
 # GN target: //src/trace_processor/sorter:sorter
 perfetto_filegroup(
     name = "src_trace_processor_sorter_sorter",

src/trace_processor/BUILD.gn

@@ -260,6 +260,7 @@ if (enable_perfetto_trace_processor_sqlite) {
       "shell:query",
       "shell:shell_utils",
       "shell:sql_packages",
+      "shell:subcommand",
       "sqlite",
       "trace_summary",
       "util:stdlib",

src/trace_processor/shell/BUILD.gn

@@ -16,10 +16,27 @@ import("../../../gn/perfetto.gni")
 
 source_set("subcommand") {
   sources = [
+    "common_flags.cc",
+    "common_flags.h",
+    "query_subcommand.cc",
+    "query_subcommand.h",
     "subcommand.cc",
     "subcommand.h",
   ]
-  deps = [ "../../../gn:default_deps" ]
+  deps = [
+    ":metatrace",
+    ":query",
+    ":shell_utils",
+    ":sql_packages",
+    "../../../gn:default_deps",
+    "../../../include/perfetto/ext/trace_processor:trace_processor_shell",
+    "../../../protos/perfetto/trace_processor:zero",
+    "../../base",
+    "../../base:version",
+    "../util/deobfuscation:deobfuscator",
+    "../util/symbolizer:symbolize_database",
+  ]
+  public_deps = [ "../../../include/perfetto/trace_processor:trace_processor" ]
 }
 
 source_set("interactive") {
@@ -112,5 +129,6 @@ source_set("unittests") {
     ":subcommand",
     "../../../gn:default_deps",
     "../../../gn:gtest_and_gmock",
+    "../../base",
   ]
 }