Fix/suppress hwui google-explicit-constructor warnings

* Add explicit to conversion constructors/operators
* Use NOLINT or NOLINTNEXTLINE to suppress warnings on intended converters

Bug: 28341362
Test: make with WITH_TIDY=1 DEFAULT_GLOBAL_TIDY_CHECKS=-*,google-explicit-constructor
Change-Id: I8c6ebb99679b0a71251024d70a13f8164e67db5e
diff --git a/libs/hwui/service/GraphicsStatsService.cpp b/libs/hwui/service/GraphicsStatsService.cpp
index 29e4256..8a16b20 100644
--- a/libs/hwui/service/GraphicsStatsService.cpp
+++ b/libs/hwui/service/GraphicsStatsService.cpp
@@ -48,7 +48,7 @@
 
 class FileDescriptor {
 public:
-    FileDescriptor(int fd) : mFd(fd) {}
+    explicit FileDescriptor(int fd) : mFd(fd) {}
     ~FileDescriptor() {
         if (mFd != -1) {
             close(mFd);
@@ -56,7 +56,7 @@
         }
     }
     bool valid() { return mFd != -1; }
-    operator int() { return mFd; }
+    operator int() { return mFd; } // NOLINT(google-explicit-constructor)
 
 private:
     int mFd;
@@ -64,7 +64,7 @@
 
 class FileOutputStreamLite : public io::ZeroCopyOutputStream {
 public:
-    FileOutputStreamLite(int fd) : mCopyAdapter(fd), mImpl(&mCopyAdapter) {}
+    explicit FileOutputStreamLite(int fd) : mCopyAdapter(fd), mImpl(&mCopyAdapter) {}
     virtual ~FileOutputStreamLite() {}
 
     int GetErrno() { return mCopyAdapter.mErrno; }
@@ -82,7 +82,7 @@
         int mFd;
         int mErrno = 0;
 
-        FDAdapter(int fd) : mFd(fd) {}
+        explicit FDAdapter(int fd) : mFd(fd) {}
         virtual ~FDAdapter() {}
 
         virtual bool Write(const void* buffer, int size) override {