simpleperf: enable .clang-format

Use the 2-space configuration by default and disable any formatting for
the demo/ subdirectory. The following command was used to generate this
change:

  $ find . \( -name \*.cpp -o -name \*.h \) -exec clang-format \
    --style=file -i {} \;

Test: mm
Change-Id: I89ec1f18f6e352f40cfa1a770087f3b586b1d7cb
diff --git a/simpleperf/cmd_kmem_test.cpp b/simpleperf/cmd_kmem_test.cpp
index 0fa3066..56ab91b 100644
--- a/simpleperf/cmd_kmem_test.cpp
+++ b/simpleperf/cmd_kmem_test.cpp
@@ -44,14 +44,12 @@
                               ReportResult* result) {
   result->success = false;
   TemporaryFile tmp_file;
-  std::vector<std::string> args = {"report", "-i", perf_data, "-o",
-                                   tmp_file.path};
+  std::vector<std::string> args = {"report", "-i", perf_data, "-o", tmp_file.path};
   args.insert(args.end(), additional_args.begin(), additional_args.end());
   ASSERT_TRUE(KmemCmd()->Run(args));
   ASSERT_TRUE(android::base::ReadFileToString(tmp_file.path, &result->content));
   ASSERT_TRUE(!result->content.empty());
-  std::vector<std::string> raw_lines =
-      android::base::Split(result->content, "\n");
+  std::vector<std::string> raw_lines = android::base::Split(result->content, "\n");
   result->lines.clear();
   for (const auto& line : raw_lines) {
     std::string s = android::base::Trim(line);
@@ -64,16 +62,14 @@
 }
 
 static void KmemReportFile(const std::string& perf_data,
-                           const std::vector<std::string>& additional_args,
-                           ReportResult* result) {
+                           const std::vector<std::string>& additional_args, ReportResult* result) {
   KmemReportRawFile(GetTestData(perf_data), additional_args, result);
 }
 
 #if defined(__linux__)
 #include "environment.h"
 
-static bool RunKmemRecordCmd(std::vector<std::string> v,
-                             const char* output_file = nullptr) {
+static bool RunKmemRecordCmd(std::vector<std::string> v, const char* output_file = nullptr) {
   std::unique_ptr<TemporaryFile> tmpfile;
   std::string out_file;
   if (output_file != nullptr) {
@@ -130,9 +126,7 @@
   ReportResult result;
   KmemReportFile(
       PERF_DATA_WITH_KMEM_SLAB_CALLGRAPH_RECORD,
-      {"--slab-sort",
-       "hit,caller,ptr,bytes_req,bytes_alloc,fragment,gfp_flags,pingpong"},
-      &result);
+      {"--slab-sort", "hit,caller,ptr,bytes_req,bytes_alloc,fragment,gfp_flags,pingpong"}, &result);
   ASSERT_TRUE(result.success);
   ASSERT_NE(result.content.find("Ptr"), std::string::npos);
   ASSERT_NE(result.content.find("GfpFlags"), std::string::npos);