[aapt2] Improve dump chunks for string pools, fix diff

- `dump chunks` command now prints extra header data for the
  string pool, and outputs all style information for styled
  strings.

- `diff` command used to only correctly compare the first span
  in the StyledString data type, making them appear different
  if there was a string with more than one span

Flag: EXEMPT bugfix
Test: atest aapt2_tests
Change-Id: I377718c03d6a464cb4db22399b0f067e6a6e04d6
diff --git a/tools/aapt2/cmd/Diff.cpp b/tools/aapt2/cmd/Diff.cpp
index 5bfc732..6da3176 100644
--- a/tools/aapt2/cmd/Diff.cpp
+++ b/tools/aapt2/cmd/Diff.cpp
@@ -106,7 +106,7 @@
   if (!value_a->Equals(value_b)) {
     std::stringstream str_stream;
     str_stream << "value " << pkg_a.name << ":" << type_a.named_type << "/" << entry_a.name
-               << " config=" << config_value_a->config << " does not match:\n";
+               << " config='" << config_value_a->config << "' does not match:\n";
     value_a->Print(&str_stream);
     str_stream << "\n vs \n";
     value_b->Print(&str_stream);